This document summarizes key differences between prokaryotic and eukaryotic genomes. Prokaryotic genomes are typically smaller, usually contained in a single circular DNA molecule within the nucleoid. The DNA is highly compacted via supercoiling. Genes have compact organization with little non-coding DNA. Operons, where genes are expressed as a unit, are common. Repetitive DNA, transposons, and pathogenicity islands can be transferred horizontally and influence virulence. In contrast, eukaryotic genomes are larger with linear chromosomes, more non-coding DNA, introns, and complex gene regulation.
Prokaryotic genomes are circular, double-stranded DNA contained within the nucleoid. They vary in length but are generally a few million base pairs. DNA supercoiling allows for tight packing of the genome.
Eukaryotic genomes are linear chromosomes associated with histone proteins within the nucleus. The DNA is wrapped around histone octamers to form nucleosomes, compacting the genome. Eukaryotic genomes are generally larger and contain more DNA than prokaryotic genomes.
Key differences between prokaryotic and eukaryotic genomes include genome size, number of chromosomes, ploidy level, association with histones, and method of compaction.
The document discusses genome organization in eukaryotes. It begins by defining the genome as an organism's entire hereditary information, encoded in DNA or RNA. In eukaryotes, DNA is associated with histone proteins to form chromatin fibers, which condense into chromosomes. The document then discusses various levels of chromatin organization, from DNA wrapping around nucleosomes to form beads on a string, to higher-order folding forming metaphase chromosomes. Chromatin exists in two types - loosely packed euchromatin and tightly packed heterochromatin. Overall, the document provides an overview of eukaryotic genome and chromatin organization from nucleosomes to chromosomes.
Genome organization of prokaryotes and eukaryotesSuganyaPaulraj
1. Prokaryotic genetic material is usually a single, circular chromosome located in the nucleoid region. Eukaryotic genetic material is contained within the nucleus in the form of linear chromosomes composed of DNA and proteins.
2. Chromosomes contain genes and vary in number between species. Eukaryotic chromosomes are packaged with histone proteins into chromatin and can exist in condensed or uncondensed states.
3. Genetic material exists in different structural and functional states between prokaryotes and eukaryotes.
Gene silencing is the regulation of gene expression in a cell to prevent the expression of a certain gene. Gene silencing can occur during either transcription or translation and is often used in research.
This document summarizes homologous recombination in eukaryotes and bacteria. In eukaryotes, homologous recombination repairs double-strand DNA breaks through either the double-strand break repair (DSBR) pathway or synthesis-dependent strand annealing (SDSA) pathway. The DSBR pathway forms double Holliday junctions that are resolved to result in crossover or non-crossover products. In bacteria, the RecBCD pathway repairs double-strand breaks and the RecF pathway repairs single-strand gaps. Both pathways involve strand invasion and branch migration to facilitate homologous recombination.
RECOMBINATION MOLECULAR BIOLOGY PPT UPDATED new.pptxSabahat Ali
This ppt is about recombination and where it occurs. Types of recombination and models of recombination along with many factors in prokaryotic and eukaryotic recombination
Chromosome walking jumping transposon tagging map based cloningPromila Sheoran
Chromosome walking, jumping, and transposon tagging are techniques used for gene mapping and cloning. Chromosome walking involves isolating overlapping DNA fragments in steps to characterize large chromosome regions. Chromosome jumping uses rare cutting enzymes to isolate larger DNA fragments spanning hundreds of kb. Transposon tagging involves inducing transposon insertion mutations, identifying the disrupted gene, and using the transposon as a tag to clone the gene. Map-based cloning localizes a gene of interest by identifying closely linked markers, screening libraries to find flanking markers, and identifying the gene between markers through complementation tests.
Prokaryotic genomes are circular, double-stranded DNA contained within the nucleoid. They vary in length but are generally a few million base pairs. DNA supercoiling allows for tight packing of the genome.
Eukaryotic genomes are linear chromosomes associated with histone proteins within the nucleus. The DNA is wrapped around histone octamers to form nucleosomes, compacting the genome. Eukaryotic genomes are generally larger and contain more DNA than prokaryotic genomes.
Key differences between prokaryotic and eukaryotic genomes include genome size, number of chromosomes, ploidy level, association with histones, and method of compaction.
The document discusses genome organization in eukaryotes. It begins by defining the genome as an organism's entire hereditary information, encoded in DNA or RNA. In eukaryotes, DNA is associated with histone proteins to form chromatin fibers, which condense into chromosomes. The document then discusses various levels of chromatin organization, from DNA wrapping around nucleosomes to form beads on a string, to higher-order folding forming metaphase chromosomes. Chromatin exists in two types - loosely packed euchromatin and tightly packed heterochromatin. Overall, the document provides an overview of eukaryotic genome and chromatin organization from nucleosomes to chromosomes.
Genome organization of prokaryotes and eukaryotesSuganyaPaulraj
1. Prokaryotic genetic material is usually a single, circular chromosome located in the nucleoid region. Eukaryotic genetic material is contained within the nucleus in the form of linear chromosomes composed of DNA and proteins.
2. Chromosomes contain genes and vary in number between species. Eukaryotic chromosomes are packaged with histone proteins into chromatin and can exist in condensed or uncondensed states.
3. Genetic material exists in different structural and functional states between prokaryotes and eukaryotes.
Gene silencing is the regulation of gene expression in a cell to prevent the expression of a certain gene. Gene silencing can occur during either transcription or translation and is often used in research.
This document summarizes homologous recombination in eukaryotes and bacteria. In eukaryotes, homologous recombination repairs double-strand DNA breaks through either the double-strand break repair (DSBR) pathway or synthesis-dependent strand annealing (SDSA) pathway. The DSBR pathway forms double Holliday junctions that are resolved to result in crossover or non-crossover products. In bacteria, the RecBCD pathway repairs double-strand breaks and the RecF pathway repairs single-strand gaps. Both pathways involve strand invasion and branch migration to facilitate homologous recombination.
RECOMBINATION MOLECULAR BIOLOGY PPT UPDATED new.pptxSabahat Ali
This ppt is about recombination and where it occurs. Types of recombination and models of recombination along with many factors in prokaryotic and eukaryotic recombination
Chromosome walking jumping transposon tagging map based cloningPromila Sheoran
Chromosome walking, jumping, and transposon tagging are techniques used for gene mapping and cloning. Chromosome walking involves isolating overlapping DNA fragments in steps to characterize large chromosome regions. Chromosome jumping uses rare cutting enzymes to isolate larger DNA fragments spanning hundreds of kb. Transposon tagging involves inducing transposon insertion mutations, identifying the disrupted gene, and using the transposon as a tag to clone the gene. Map-based cloning localizes a gene of interest by identifying closely linked markers, screening libraries to find flanking markers, and identifying the gene between markers through complementation tests.
Bacteria possess two genetic structures - the chromosome and plasmids. Plasmids are circular DNA molecules that are not essential for survival but can carry genes for virulence or antibiotic resistance. Bacteria exchange genetic information through transformation, transduction, and conjugation. Transformation involves uptake of naked DNA, transduction uses bacteriophages to transfer DNA, and conjugation requires cell-to-cell contact. Recombination and mutation contribute to genetic variability within bacterial populations. Restriction enzymes help prevent uptake of foreign DNA that is not properly modified.
DNA probes are short segments of DNA or RNA that are labeled to allow for detection when bound to complementary nucleic acid sequences. Probes can be labeled through various methods, including fluorescent dyes, isotopic labeling using radioactive atoms, or non-isotopic labeling using molecules like biotin. Labeled probes are used in techniques like Southern blotting, PCR, and in situ hybridization to detect specific DNA or RNA sequences and analyze genetic material.
This document discusses the organization of genetic material in prokaryotic and eukaryotic cells. It begins by defining key terms like genome and describing the overall structure of genetic material. It then contrasts prokaryotic and eukaryotic cells, noting things like prokaryotes having circular DNA without introns while eukaryotes have linear chromosomes and mRNA splicing. The document also discusses specific genetic elements like plasmids, viruses, and organelles. It provides details on their size, structure and content. Finally, the sizes of some viral, bacterial, and eukaryotic genomes are compared.
This document discusses transposable elements (TEs), which are segments of DNA that can change positions within the genome. It classifies TEs into two classes based on their mechanism of transposition. Class 1 elements use a "cut and paste" mechanism involving transposase, while Class 2 retrotransposons use reverse transcriptase in a "copy and paste" mechanism. Examples of TEs discussed include Ac-Ds elements in maize, P elements in Drosophila, and LINEs and SINEs in humans. The effects of TE insertion include gene mutation, changes in gene regulation, gene duplication, deletion, and chromosome rearrangements. Applications of TEs include their use as cloning vectors and providing raw material for evolution
Chromosome walking is a method used to isolate and clone a particular gene or allele through positional cloning. It involves using overlapping clones that contain DNA fragments near the target gene to "walk" through the chromosome until reaching the gene. Each successive clone is tested to map its precise location until eventually reaching the target gene. Chromosome walking was developed in the early 1980s and can be used to analyze genetically transmitted diseases and find single nucleotide polymorphisms. However, it has limitations such as being a slow process and difficulty walking through repeated sequences.
DNA footprinting is a technique used to identify protein binding regions on DNA. It involves treating DNA with nucleases like DNase I, which will degrade the DNA except for regions bound by proteins. These protected regions, called footprints, can identify transcription factor binding sites that regulate gene expression. The technique was originally developed in 1978 to study the binding specificity of the lac repressor protein, and it provides information on DNA-protein interactions and transcriptional regulation.
The document discusses genetic recombination and site-specific recombination. It describes the Meselson-Radding model of genetic recombination, which involves a single-strand nick that allows DNA polymerase to extend the 3' end and displace the other strand, forming a D loop structure. Site-specific recombination involves recombinases cutting DNA at specific recognition sequences and rejoining the strands to form a Holliday junction intermediate. Examples discussed include bacteriophage lambda integration into E. coli DNA, which is mediated by lambda integrase recombining attP and attB sites.
Transduction is a mode of genetic transfer between bacteria mediated by bacteriophages. During viral replication, fragments of bacterial DNA can become packaged within viral particles. These particles may then infect other bacteria and insert the donor DNA into the recipient genome. There are two types of transduction - generalized, where any bacterial DNA fragment can be transferred, and specialized, where only DNA near the site of viral integration is transferred. Cotransduction frequencies can also be used to map the relative locations of bacterial genes, as genes closer together are more likely to be cotransferred within the same viral particle. Transduction is useful for genetic engineering and mapping bacterial chromosomes.
Retrotransposons are genetic elements that copy and paste themselves throughout the genome using an RNA intermediate and reverse transcription. There are two main types: LTR retrotransposons, which mimic retroviruses through reverse transcription of an RNA copy into DNA; and non-LTR retrotransposons like LINEs and SINEs. LINEs (Long Interspersed Nuclear Elements) are autonomous retrotransposons over 6kb with endonuclease and reverse transcriptase proteins. SINEs (Short Interspersed Nuclear Elements) are shorter than 300bp and non-autonomous, relying on LINEs to reverse transcribe themselves.
Site directed mutgenesis, OLIGONUCLEOTIDE DIRECTED MUTAGENESIS Vipin Shukla
INTRODUCTION, HISTORY, MUTATION, DIRECTED MUTAGENESIS,BASIC MECHANISM OF SITE DIRECTED MUTAGENESIS,METHOD FOR SITE DIRECTED MUTATIONS,THE SINGLE PRIMER METHOD, CASETTEE MUTAGENESIS, PCR-SITED DIRECTED MUTAGENESIS, APPLICATION OF SITE DIRECTED MUTAGENESIS.
The document discusses methods for directed mutagenesis in DNA. It describes how early methods involved random mutagenesis using physical and chemical mutagens. Modern techniques now allow directed mutagenesis through recombinant DNA methods, allowing specific mutations even at the single nucleotide level. Several directed mutagenesis methods are outlined, including oligonucleotide-mediated mutagenesis and PCR-based mutagenesis. Important discoveries in directed mutagenesis include methods developed for prokaryotes and eukaryotes in the 1980s, for which Mario Capecchi and Oliver Smithies received the Nobel Prize.
The document discusses the lambda (λ) phage repressor system that regulates the virus's life cycle pathways. The λ phage can either undergo lytic or lysogenic cycles. In the lytic cycle, the phage replicates itself many times and bursts the host cell. In the lysogenic cycle, the phage genome integrates into the host genome without replicating. The choice between these cycles is controlled by a molecular switch involving the CI and CRO repressor proteins. CI activates the lysogenic pathway by binding operator sites and blocking transcription of lytic genes. CRO activates the lytic pathway by blocking CI transcription. Environmental conditions like host stress can trigger a switch from lysogenic to lytic cycling.
Automated DNA sequencing ; Protein sequencingRima Joseph
This document discusses several methods for DNA and protein sequencing. It describes automated DNA sequencing which is based on the Sanger method but uses fluorescent labels and allows direct computer storage of sequence data. It then discusses various methods for protein sequencing including purification, amino acid composition analysis, N-terminal sequencing using Edman degradation or other methods, C-terminal sequencing, breaking disulfide bonds, cleaving the protein into peptides, ordering peptides by overlap, and locating disulfide bonds. Newer methods discussed are using genomic data and mass spectrometry techniques.
Genomic and cDNA libraries are constructed to isolate genes of interest from organisms. Genomic libraries contain total chromosomal DNA while cDNA libraries contain mRNA from specific cell types. DNA is digested and ligated into vectors to clone fragments. Libraries are screened using probes and PCR to identify clones containing genes of interest. cDNA libraries are useful for studying eukaryotic gene expression as they contain mRNA from specific cells. Thousands of clones may need to be screened to have high probability of isolating a particular gene fragment.
Genome mapping involves locating genes on chromosomes and determining the relative distances between genes. There are two main types of maps: genetic linkage maps which show the arrangement of genes based on their inheritance patterns, and physical maps which provide actual distances between landmarks on chromosomes. Physical maps can be further divided into cytogenetic maps, radiation hybrid maps, and sequence maps, with the complete DNA sequence being the ultimate physical map. Mapping methods include linkage analysis using genetic markers, as well as transformation, transduction, and sequencing of bacterial artificial chromosomes (BACs) and yeast artificial chromosomes (YACs).
Genome organisation in eukaryotes...........!!!!!!!!!!!manish chovatiya
This document discusses the organization of eukaryotic genomes. It explains that eukaryotic genomes are much larger than prokaryotic genomes, with most of the DNA being non-coding. Eukaryotic genomes contain multiple linear chromosomes, introns, repetitive sequences, and both coding and non-coding RNA genes. The document also describes different types of repetitive elements like tandem repeats, transposons, retrotransposons, LINEs, SINEs and their roles in increasing genome size. Overall, the document provides an overview of the complex structure of eukaryotic genomes compared to simpler prokaryotic genomes.
Genome organization in prokaryotes(molecular biology)IndrajaDoradla
1. In prokaryotes, the genome is located in an irregularly shaped region within the cell called the nucleoid, which is not surrounded by a membrane like the eukaryotic nucleus.
2. The prokaryotic genome is generally a circular piece of DNA that can exist in multiple copies and ranges in length but is at least a few million base pairs. It is packaged into the nucleoid through supercoiling facilitated by nucleoid-associated proteins.
3. DNA supercoiling allows for very long strands of DNA to be tightly packaged into a prokaryotic cell. This involves the introduction of plectonemic supercoils that twist the DNA into loops and wind it around nucle
Bacterial genomes provide insights into bacterial function, origins, and diversity. They range in size from 0.6 to over 10 megabase pairs. Analysis of bacterial genomes reveals gene content and organization, as well as base pair composition trends. Bacterial chromosomes are typically circular and condensed via supercoiling, though some bacteria have linear or multiple chromosomes. Genome analysis techniques like GC skew help locate origins of replication.
Bacteria possess two genetic structures - the chromosome and plasmids. Plasmids are circular DNA molecules that are not essential for survival but can carry genes for virulence or antibiotic resistance. Bacteria exchange genetic information through transformation, transduction, and conjugation. Transformation involves uptake of naked DNA, transduction uses bacteriophages to transfer DNA, and conjugation requires cell-to-cell contact. Recombination and mutation contribute to genetic variability within bacterial populations. Restriction enzymes help prevent uptake of foreign DNA that is not properly modified.
DNA probes are short segments of DNA or RNA that are labeled to allow for detection when bound to complementary nucleic acid sequences. Probes can be labeled through various methods, including fluorescent dyes, isotopic labeling using radioactive atoms, or non-isotopic labeling using molecules like biotin. Labeled probes are used in techniques like Southern blotting, PCR, and in situ hybridization to detect specific DNA or RNA sequences and analyze genetic material.
This document discusses the organization of genetic material in prokaryotic and eukaryotic cells. It begins by defining key terms like genome and describing the overall structure of genetic material. It then contrasts prokaryotic and eukaryotic cells, noting things like prokaryotes having circular DNA without introns while eukaryotes have linear chromosomes and mRNA splicing. The document also discusses specific genetic elements like plasmids, viruses, and organelles. It provides details on their size, structure and content. Finally, the sizes of some viral, bacterial, and eukaryotic genomes are compared.
This document discusses transposable elements (TEs), which are segments of DNA that can change positions within the genome. It classifies TEs into two classes based on their mechanism of transposition. Class 1 elements use a "cut and paste" mechanism involving transposase, while Class 2 retrotransposons use reverse transcriptase in a "copy and paste" mechanism. Examples of TEs discussed include Ac-Ds elements in maize, P elements in Drosophila, and LINEs and SINEs in humans. The effects of TE insertion include gene mutation, changes in gene regulation, gene duplication, deletion, and chromosome rearrangements. Applications of TEs include their use as cloning vectors and providing raw material for evolution
Chromosome walking is a method used to isolate and clone a particular gene or allele through positional cloning. It involves using overlapping clones that contain DNA fragments near the target gene to "walk" through the chromosome until reaching the gene. Each successive clone is tested to map its precise location until eventually reaching the target gene. Chromosome walking was developed in the early 1980s and can be used to analyze genetically transmitted diseases and find single nucleotide polymorphisms. However, it has limitations such as being a slow process and difficulty walking through repeated sequences.
DNA footprinting is a technique used to identify protein binding regions on DNA. It involves treating DNA with nucleases like DNase I, which will degrade the DNA except for regions bound by proteins. These protected regions, called footprints, can identify transcription factor binding sites that regulate gene expression. The technique was originally developed in 1978 to study the binding specificity of the lac repressor protein, and it provides information on DNA-protein interactions and transcriptional regulation.
The document discusses genetic recombination and site-specific recombination. It describes the Meselson-Radding model of genetic recombination, which involves a single-strand nick that allows DNA polymerase to extend the 3' end and displace the other strand, forming a D loop structure. Site-specific recombination involves recombinases cutting DNA at specific recognition sequences and rejoining the strands to form a Holliday junction intermediate. Examples discussed include bacteriophage lambda integration into E. coli DNA, which is mediated by lambda integrase recombining attP and attB sites.
Transduction is a mode of genetic transfer between bacteria mediated by bacteriophages. During viral replication, fragments of bacterial DNA can become packaged within viral particles. These particles may then infect other bacteria and insert the donor DNA into the recipient genome. There are two types of transduction - generalized, where any bacterial DNA fragment can be transferred, and specialized, where only DNA near the site of viral integration is transferred. Cotransduction frequencies can also be used to map the relative locations of bacterial genes, as genes closer together are more likely to be cotransferred within the same viral particle. Transduction is useful for genetic engineering and mapping bacterial chromosomes.
Retrotransposons are genetic elements that copy and paste themselves throughout the genome using an RNA intermediate and reverse transcription. There are two main types: LTR retrotransposons, which mimic retroviruses through reverse transcription of an RNA copy into DNA; and non-LTR retrotransposons like LINEs and SINEs. LINEs (Long Interspersed Nuclear Elements) are autonomous retrotransposons over 6kb with endonuclease and reverse transcriptase proteins. SINEs (Short Interspersed Nuclear Elements) are shorter than 300bp and non-autonomous, relying on LINEs to reverse transcribe themselves.
Site directed mutgenesis, OLIGONUCLEOTIDE DIRECTED MUTAGENESIS Vipin Shukla
INTRODUCTION, HISTORY, MUTATION, DIRECTED MUTAGENESIS,BASIC MECHANISM OF SITE DIRECTED MUTAGENESIS,METHOD FOR SITE DIRECTED MUTATIONS,THE SINGLE PRIMER METHOD, CASETTEE MUTAGENESIS, PCR-SITED DIRECTED MUTAGENESIS, APPLICATION OF SITE DIRECTED MUTAGENESIS.
The document discusses methods for directed mutagenesis in DNA. It describes how early methods involved random mutagenesis using physical and chemical mutagens. Modern techniques now allow directed mutagenesis through recombinant DNA methods, allowing specific mutations even at the single nucleotide level. Several directed mutagenesis methods are outlined, including oligonucleotide-mediated mutagenesis and PCR-based mutagenesis. Important discoveries in directed mutagenesis include methods developed for prokaryotes and eukaryotes in the 1980s, for which Mario Capecchi and Oliver Smithies received the Nobel Prize.
The document discusses the lambda (λ) phage repressor system that regulates the virus's life cycle pathways. The λ phage can either undergo lytic or lysogenic cycles. In the lytic cycle, the phage replicates itself many times and bursts the host cell. In the lysogenic cycle, the phage genome integrates into the host genome without replicating. The choice between these cycles is controlled by a molecular switch involving the CI and CRO repressor proteins. CI activates the lysogenic pathway by binding operator sites and blocking transcription of lytic genes. CRO activates the lytic pathway by blocking CI transcription. Environmental conditions like host stress can trigger a switch from lysogenic to lytic cycling.
Automated DNA sequencing ; Protein sequencingRima Joseph
This document discusses several methods for DNA and protein sequencing. It describes automated DNA sequencing which is based on the Sanger method but uses fluorescent labels and allows direct computer storage of sequence data. It then discusses various methods for protein sequencing including purification, amino acid composition analysis, N-terminal sequencing using Edman degradation or other methods, C-terminal sequencing, breaking disulfide bonds, cleaving the protein into peptides, ordering peptides by overlap, and locating disulfide bonds. Newer methods discussed are using genomic data and mass spectrometry techniques.
Genomic and cDNA libraries are constructed to isolate genes of interest from organisms. Genomic libraries contain total chromosomal DNA while cDNA libraries contain mRNA from specific cell types. DNA is digested and ligated into vectors to clone fragments. Libraries are screened using probes and PCR to identify clones containing genes of interest. cDNA libraries are useful for studying eukaryotic gene expression as they contain mRNA from specific cells. Thousands of clones may need to be screened to have high probability of isolating a particular gene fragment.
Genome mapping involves locating genes on chromosomes and determining the relative distances between genes. There are two main types of maps: genetic linkage maps which show the arrangement of genes based on their inheritance patterns, and physical maps which provide actual distances between landmarks on chromosomes. Physical maps can be further divided into cytogenetic maps, radiation hybrid maps, and sequence maps, with the complete DNA sequence being the ultimate physical map. Mapping methods include linkage analysis using genetic markers, as well as transformation, transduction, and sequencing of bacterial artificial chromosomes (BACs) and yeast artificial chromosomes (YACs).
Genome organisation in eukaryotes...........!!!!!!!!!!!manish chovatiya
This document discusses the organization of eukaryotic genomes. It explains that eukaryotic genomes are much larger than prokaryotic genomes, with most of the DNA being non-coding. Eukaryotic genomes contain multiple linear chromosomes, introns, repetitive sequences, and both coding and non-coding RNA genes. The document also describes different types of repetitive elements like tandem repeats, transposons, retrotransposons, LINEs, SINEs and their roles in increasing genome size. Overall, the document provides an overview of the complex structure of eukaryotic genomes compared to simpler prokaryotic genomes.
Genome organization in prokaryotes(molecular biology)IndrajaDoradla
1. In prokaryotes, the genome is located in an irregularly shaped region within the cell called the nucleoid, which is not surrounded by a membrane like the eukaryotic nucleus.
2. The prokaryotic genome is generally a circular piece of DNA that can exist in multiple copies and ranges in length but is at least a few million base pairs. It is packaged into the nucleoid through supercoiling facilitated by nucleoid-associated proteins.
3. DNA supercoiling allows for very long strands of DNA to be tightly packaged into a prokaryotic cell. This involves the introduction of plectonemic supercoils that twist the DNA into loops and wind it around nucle
Bacterial genomes provide insights into bacterial function, origins, and diversity. They range in size from 0.6 to over 10 megabase pairs. Analysis of bacterial genomes reveals gene content and organization, as well as base pair composition trends. Bacterial chromosomes are typically circular and condensed via supercoiling, though some bacteria have linear or multiple chromosomes. Genome analysis techniques like GC skew help locate origins of replication.
This document summarizes key aspects of genome organization in prokaryotes. It notes that prokaryotes like E. coli have a single circular chromosome composed of DNA that is compacted into a nucleoid structure. The DNA is highly condensed via supercoiling facilitated by enzymes like topoisomerases. Prokaryotic genomes are also typically smaller than eukaryotic ones and can contain extra DNA on plasmids that are exchanged between bacteria.
DNA organization or Genetic makeup in Prokaryotic and Eukaryotic SystemsBir Bahadur Thapa
DNA organization or Genetic makeup in Prokaryotic and Eukaryotic Systems!! It is prepared under the syllabus of Tribhuwan University, Nepal, MSc. 3rd Semester as a lecture class!!
1. Mutations are changes in the nucleotide sequence of DNA that can arise spontaneously during DNA replication or due to damage from mutagens.
2. DNA repair enzymes work to minimize mutations by correcting errors during replication or reacting to damaged DNA.
3. If a mismatch introduced during replication is not repaired, it will become a permanent mutation when that region is replicated again.
This document provides an introduction to genomics, proteomics, and comparative genomics. It discusses the central dogma of molecular biology involving DNA replication, transcription, and translation. It describes DNA and RNA structure and explains how genetic information flows from DNA to protein. The document also discusses genome sequencing, gene mapping, and how comparative analysis of genomes from different species can provide insights into evolutionary relationships and biological functions.
1. The document discusses microbial genetics and the flow of genetic information. It defines key terms like genetics, genes, genome, genotype, and phenotype.
2. It describes the structure of DNA and how it carries genetic information as a double-stranded molecule made up of nucleotides. DNA replication is semi-conservative and involves unwinding the strands, creating an RNA primer, and synthesizing new strands in the 5' to 3' direction.
3. The process of transcription is described, where RNA polymerase reads the genetic code from DNA and synthesizes mRNA, which is then translated to produce proteins. Both prokaryotes and eukaryotes undergo transcription but differ in initiation, processing, and coupling with
Prokaryotic genetic material differs from eukaryotes in several key ways:
1. Prokaryotes lack a membrane-bound nucleus and have their DNA located in the nucleoid. They typically have a single circular chromosome while eukaryotes have multiple linear chromosomes.
2. Prokaryotic genes are arranged in operons and expressed together, whereas eukaryotic genes each have their own promoter and are independently expressed.
3. DNA replication in prokaryotes is rapid and ongoing, starting from a single origin of replication site, while eukaryotes tightly regulate replication during the cell cycle.
The document provides an overview of the structure and functions of the cell nucleus. It discusses how DNA is tightly packaged into chromosomes through winding around histone proteins to form nucleosomes and chromatin fibers. This compact packaging allows the 100 trillion meters of DNA in the human body to fit within cell nuclei. The nucleus contains DNA, which directs gene expression, DNA replication, and cell division. RNA carries DNA's genetic instructions out of the nucleus to direct protein synthesis. Key concepts covered include DNA and RNA structure, DNA replication, transcription, translation, and the central dogma of molecular biology.
Organization of genetic materials in eukaryotes and prokaryotesBHUMI GAMETI
What is Genome ?
Types of Genome
Packaging of DNA into chromosome
GENOME ORGANIZATION IN PROKARYOTES
Plasmids
Plasmids
Nucleoid
Enzyme
GENOME ORGANIZATION IN EUKARYOTES
Chemical composition of chromatin
Nucleosome model.
Levels of DNA Packaging
Prokaryotic Genome v/s Eukaryotic Genome
This document provides an overview of microbial genetics. It discusses key topics like DNA, RNA, proteins, transcription, translation, gene regulation, and genetic variation. Regarding prokaryotes vs eukaryotes, it notes that prokaryotes lack membrane-bound organelles and their DNA is not sequestered in the nucleus. It also explains processes like DNA replication, transcription, translation, and how gene expression is regulated through operons and repressor/activator proteins binding DNA. The document outlines bacterial mechanisms of genetic variation like mutation and horizontal gene transfer through conjugation, transformation and transduction.
DNA replication is the process by which DNA copies itself during cell division. Key enzymes involved include DNA polymerase, which catalyzes the joining of nucleotides to form the new DNA strand. DNA replication occurs in three stages - initiation, elongation, and termination. In eukaryotes, initiation requires DNA polymerases α and δ, as well as other proteins. Elongation involves DNA polymerase adding nucleotides to the 3' end of the growing strand. Termination occurs when DNA polymerase reaches a replicated section of DNA and ligase joins the DNA backbone.
The document discusses the molecular structure of genes and chromosomes. It describes how DNA is organized into chromosomes, which contain both protein-coding genes and non-coding sequences. Genes contain exons and introns, and in eukaryotes genes are further organized into transcription units. Chromatin compacts the DNA into nucleosomes and higher-order structures like the 30nm fiber. Overall the document provides an overview of the molecular organization and components that make up eukaryotic genes and chromosomes.
INTRODUCTION TO DIAGNOSTIC MOLECULAR BIOLOGY.pptxRamadhaniSaidi5
Molecular biology refers to the study of biology at the molecular level, including genes, proteins, and DNA. Molecular diagnosis uses techniques from molecular biology to analyze biological markers in the genome and proteome for medical testing. The document defines key terms related to molecular biology and diagnostic molecular biology, including DNA, genes, chromosomes, nucleic acids, and their roles and structures. It discusses the significance of diagnostic molecular biology for medical testing.
Molecular biology studies the molecular basis of biological activity. It examines how molecules like nucleic acids and proteins interact in living organisms. There are two main types of nucleic acids: DNA and RNA. DNA is found in the nucleus and encodes the genetic information to make proteins. RNA also plays important roles like mRNA which helps translate DNA instructions into proteins. The central dogma of molecular biology illustrates how genetic information flows from DNA to RNA to protein.
Genetic recombination and genetic engineeringshobejee
Herbert Boyer and Stanley Cohen created the first recombinant DNA molecule in 1973, proving that genetic engineering is possible. Walter Gilbert and Frederick Sanger then developed methods to determine DNA sequences. This allowed genes to be isolated, identified, and induced to express proteins in host cells. Recombinant DNA techniques have revolutionized biology and medicine by precisely modifying genetic endowments and producing clinically useful proteins. The techniques involve using restriction enzymes to cut DNA fragments for insertion into cloning vectors like plasmids, which are then replicated in host cells to amplify the gene of interest.
The document discusses genes in prokaryotes. It defines key terms like gene, prokaryotic gene, and operon. It explains that prokaryotic genes consist of a promoter region, RNA coding sequence, and terminator region. Gene expression involves transcription and translation processes that occur in the cytoplasm. Gene regulation is achieved through repressible and inducible operons like the trp and lac operons, which are controlled by repressor and activator proteins that bind to DNA in response to environmental stimuli.
Transposons are segments of DNA that can move, or "jump", from one location in the genome to another. They were first discovered by Barbara McClintock in her studies of maize. Transposons make up over 50% of the human genome. There are two classes - Class I retrotransposons move via an RNA intermediate, while Class II transposons move directly from DNA to DNA. Transposition occurs through a "cut and paste" mechanism where the transposon is excised from one location and inserted into a new random site in the genome. While transposons can disrupt gene function, recent evidence suggests they may also help organisms adapt to environmental stress.
UNIQUE AND REPETITIVE DNA.a derailed presentationkingmaxton8
The document discusses unique and repetitive DNA sequences found in eukaryotic genomes. It defines unique DNA as sequences present in a single copy that encode for proteins. Repetitive DNA makes up a large portion of eukaryotic genomes and includes highly repetitive sequences like satellite DNA near centromeres, and moderately repetitive sequences dispersed throughout genomes like transposons. The repetitive elements are further classified based on length and copy number as tandem repeats including satellites, minisatellites and microsatellites.
This slide is special for master students (MIBS & MIFB) in UUM. Also useful for readers who are interested in the topic of contemporary Islamic banking.
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...PECB
Denis is a dynamic and results-driven Chief Information Officer (CIO) with a distinguished career spanning information systems analysis and technical project management. With a proven track record of spearheading the design and delivery of cutting-edge Information Management solutions, he has consistently elevated business operations, streamlined reporting functions, and maximized process efficiency.
Certified as an ISO/IEC 27001: Information Security Management Systems (ISMS) Lead Implementer, Data Protection Officer, and Cyber Risks Analyst, Denis brings a heightened focus on data security, privacy, and cyber resilience to every endeavor.
His expertise extends across a diverse spectrum of reporting, database, and web development applications, underpinned by an exceptional grasp of data storage and virtualization technologies. His proficiency in application testing, database administration, and data cleansing ensures seamless execution of complex projects.
What sets Denis apart is his comprehensive understanding of Business and Systems Analysis technologies, honed through involvement in all phases of the Software Development Lifecycle (SDLC). From meticulous requirements gathering to precise analysis, innovative design, rigorous development, thorough testing, and successful implementation, he has consistently delivered exceptional results.
Throughout his career, he has taken on multifaceted roles, from leading technical project management teams to owning solutions that drive operational excellence. His conscientious and proactive approach is unwavering, whether he is working independently or collaboratively within a team. His ability to connect with colleagues on a personal level underscores his commitment to fostering a harmonious and productive workplace environment.
Date: May 29, 2024
Tags: Information Security, ISO/IEC 27001, ISO/IEC 42001, Artificial Intelligence, GDPR
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Strategies for Effective Upskilling is a presentation by Chinwendu Peace in a Your Skill Boost Masterclass organisation by the Excellence Foundation for South Sudan on 08th and 09th June 2024 from 1 PM to 3 PM on each day.
How to Setup Warehouse & Location in Odoo 17 InventoryCeline George
In this slide, we'll explore how to set up warehouses and locations in Odoo 17 Inventory. This will help us manage our stock effectively, track inventory levels, and streamline warehouse operations.
LAND USE LAND COVER AND NDVI OF MIRZAPUR DISTRICT, UPRAHUL
This Dissertation explores the particular circumstances of Mirzapur, a region located in the
core of India. Mirzapur, with its varied terrains and abundant biodiversity, offers an optimal
environment for investigating the changes in vegetation cover dynamics. Our study utilizes
advanced technologies such as GIS (Geographic Information Systems) and Remote sensing to
analyze the transformations that have taken place over the course of a decade.
The complex relationship between human activities and the environment has been the focus
of extensive research and worry. As the global community grapples with swift urbanization,
population expansion, and economic progress, the effects on natural ecosystems are becoming
more evident. A crucial element of this impact is the alteration of vegetation cover, which plays a
significant role in maintaining the ecological equilibrium of our planet.Land serves as the foundation for all human activities and provides the necessary materials for
these activities. As the most crucial natural resource, its utilization by humans results in different
'Land uses,' which are determined by both human activities and the physical characteristics of the
land.
The utilization of land is impacted by human needs and environmental factors. In countries
like India, rapid population growth and the emphasis on extensive resource exploitation can lead
to significant land degradation, adversely affecting the region's land cover.
Therefore, human intervention has significantly influenced land use patterns over many
centuries, evolving its structure over time and space. In the present era, these changes have
accelerated due to factors such as agriculture and urbanization. Information regarding land use and
cover is essential for various planning and management tasks related to the Earth's surface,
providing crucial environmental data for scientific, resource management, policy purposes, and
diverse human activities.
Accurate understanding of land use and cover is imperative for the development planning
of any area. Consequently, a wide range of professionals, including earth system scientists, land
and water managers, and urban planners, are interested in obtaining data on land use and cover
changes, conversion trends, and other related patterns. The spatial dimensions of land use and
cover support policymakers and scientists in making well-informed decisions, as alterations in
these patterns indicate shifts in economic and social conditions. Monitoring such changes with the
help of Advanced technologies like Remote Sensing and Geographic Information Systems is
crucial for coordinated efforts across different administrative levels. Advanced technologies like
Remote Sensing and Geographic Information Systems
9
Changes in vegetation cover refer to variations in the distribution, composition, and overall
structure of plant communities across different temporal and spatial scales. These changes can
occur natural.
How to Add Chatter in the odoo 17 ERP ModuleCeline George
In Odoo, the chatter is like a chat tool that helps you work together on records. You can leave notes and track things, making it easier to talk with your team and partners. Inside chatter, all communication history, activity, and changes will be displayed.
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Executive Directors Chat Leveraging AI for Diversity, Equity, and InclusionTechSoup
Let’s explore the intersection of technology and equity in the final session of our DEI series. Discover how AI tools, like ChatGPT, can be used to support and enhance your nonprofit's DEI initiatives. Participants will gain insights into practical AI applications and get tips for leveraging technology to advance their DEI goals.
4. Most prokaryotic genomes are less than 5 Mb in
size, few are larger like B. megaterium , has a
huge genome of 30 Mb.
The typical prokaryote the genome is contained
in a single circular DNA molecule, localized
within the nucleoid .
THE PHYSICAL STRUCTURE OF THE
PROKARYOTIC GENOME
4
5. Human and bacterium cell
• Eukaryotic cells have
membrane-bound
compartments, which
are absent from
prokaryotes.
• The bacterial DNA is
contained in the
structure called the
nucleoid.
5
6. GENOME CAN BE NATURALLY
COMPACTED BY SUPERCOILING IT
The first feature to be recognized was
that the circular E. coli genome
is supercoiled.
• It’s the expression of strain
over a strand i.e. over or under
winding.
• No winding in linear molecule.
• circular molecule responds by
winding around itself to form a
more compact structure .
• Enzymes : Gyrase and
Topoisomerase 1.
Supercoiling : negative supercoiling. 6
8. MODEL FOR GENOME ORGANIZATION
Between 40 and 50 supercoiled loops of DNA radiate from the central protein core. One of the
loops is shown in circular form, indicating that a break has occurred in this segment of DNA,
resulting in a loss of the supercoiling.
8
9. • Bacterial DNA is attached to proteins that restrict its
ability to relax, so that rotation at a break site results in
loss of supercoiling.
• The current model has the E. coli DNA attached to a protein
core from which 40–50 supercoiled loops. Each loop contains
approximately 100 kb of supercoiled DNA, the amount of
DNA that becomes unwound after a single break.
9
10. THE GENETIC ORGANIZATION OF
THE PROKARYOTIC GENOME
• Bacterial genomes have compact organizations
very little space between genes.
• There is non-coding DNA in the E.
coli genome, but it accounts for only 11% of the
total.
• prokaryotic genomes have very little wasted
space. 10
11. OPERONS ARE CHARACTERISTIC
FEATURES OF PROKARYOTIC
GENOMES
An operon is a group of genes that are located
adjacent to one another in the genome,.
All the genes in an operon are expressed as a
single unit.
This type of arrangement is common in
prokaryotic genomes. Eg : lactose operon.
11
12. HUMAN GENOME
• 22 autosome pairs + 2
sex chromosomes
• 3 billion base pairs in the
haploid genome
12
14. MUCH DNA IN LARGE GENOMES IS
NON-CODING
• Contributors to the non-coding DNA include:
• Introns in genes
• Regulatory elements of genes
• Multiple copies of genes, including pseudogenes
• Intergenic sequences
• Interspersed repeats
14
16. • All eukaryotes have at least two chromosomes and the
DNA molecules are always linear.
• The only variability at this level of eukaryotic genome
structure lies with chromosome number, which appears to
be unrelated to the biological features of the organism.
16
18. Definition:
Stretches of DNA that repeat themselves throughout a
Genome , either in tandem or interspersed along the
Genome. These stretches can comprise up to fifty
Percent or more of an organism’s DNA.
* It can have a structural function (such as telomere)
or can comprise sequences of no known function
18
19. Some of its DNA use as a useful
purpose
but significant proportional is
of uncertain purpose & may be
treated as JUNK DNA OR
SELFISH DNA
19
20. • Refers to non-coding tandem
repeating sequences.
• These are generally short
sequence repeats (upto 60
base pair long).
• These appear as small dark
bands in CsCl density
gradient analysis test.
Satellite DNA Repetitive DNA
20
• It is the non-coding DNA
with tandem or
interspersed sequences.
• These can be few base pairs
to hundreds or thousands
of base pairs long.
• In CsCl density gradient
analysis, They appear as
light bands
29. STUDY OF REPETITIVE DNA IS IMPORTANT
BECAUSE
• Repeats Drive Evolution in Diverse Ways
• Repetitive DNA are generally not found to
have any function
•Homology searches need repeat masking
• Repeat also contain information about
parentage 29
32. IN PROKARYOTES
DNA forms a single band in
gradient while cscl density is equal
to density of DNA having 50% of
GC base pair
32
33. IN EUKARYOTES
•Cscl density gradient analysis ususally reveals
presence of 1 large band & one to several
small bands.
•And these several bands are called satellite
band having DNA reveals repeating sequences
of various links in different organisms. 33
34. A repetitive DNA sequences will be
identified as
Satellite DNA only if sequences has base
composition
different from that of “MAINBAND DNA”
34
35. TYPES OF REPETITIVE DNA
•SATELLITE DNA
•MINI SATELLITE DNA
•MICRO SATELLITE DNA
•TRANSPOSABLE ELEMENTS
•LINES,SINES & OTHER
RETROSEQUENCES
35
36. 1. SATELLITE DNA
• Form distant bands
• Location - heterochromatin region of
chromosome
• Unit - 5 – 300 bp depending on species
• Repeat - 105 – 106 times
• There are 10 distinct types of satellite dna
Egs – centromeric DNA , telomeric DNA
36
37. 2. MINI SATELLITE DNA
• Repeat – generally 20 – 50 times
(1000 – 5000 bp long)
• Location – euchromatic region of chromosomes
• Egs – DNA finger prints (variable no. tandem repeats)
37
38. 3. MICRO SATELLITE
• Units – 2 – 4 bp
• Repeats – 10 – 100 times in a
genome
• Location – euchromatin region
of chromosome
38
These Repetitive DNA s Can Cause Diseases:
Fragile X Syndrome – “CGG” is repeated.
39. 4. TRANSPOSABLE ELEMENTS
• These are called transposable elements because of transposons that
change their position in genome.
• Interspaced repeats have the capability to “move around” in the
genome.
• Transposition in germ cells are passed down to progeny resulting in an
accumulation in the genome.
• Transposons provide a mechanism for bringing about DNA
rearrangements throughout evolution.
• Adjacent DNA sequences sometimes mobilized
39
42. 3 PRINCIPLE CLASSES OF TRANSPOSONS
1. DNA transposons:
move using cut and paste or replicative
mechanism
2. Virus-like retrotransposons
(long terminal repeat [LTR] retrotransposons):
RNA intermediate, includes retroviruses
3. Poly-A retrotransposons
(nonviral retrotransposons):
RNA intermediate
42
43. CUT AND PASTE MECHANISM OF TRANSPOSITION:
• Nonreplicative
1.Transposase (usually 2 or 4 subunits) binds
terminal inverted repeats
2.Brings 2 ends together stable protein complex
called transpososome
3.Transposase cleaves one DNA strand at each end at
junction between transposon DNA and host DNA
transposon sequence terminates with free 3’-OH
groups at each end
4.Other DNA strands cut by various mechanisms
transposon excised
43
44. Cut and paste mechanism of transposition
5. 3’-OH ends of transposon DNA attack
DNA phosphodiester bonds at site of
new insertion (target DNA)
6. Nicks introduced in other target DNA
strands few nucleotides apart
transposon joined via reaction called
DNA strand transfer
7. Few nucleotides between nicks leaves
small ss gaps filled in by host DNA
repair polymerase small target site
duplications on either side transposon
8. DNA ligase seals final nicks
9. Ds break where transposon left
repaired by homologous
recombination 44
45. REPLICATIVE TRANSPOSITION:
• Transposon DNA replicated during each round of
transposition
1.Transposase assembles on each end of
transposon to form transpososome
2.Transposase introduces nicks at junctions
between transposon and flanking host DNA
generates 3’-OH ends on transposon (but
transposon NOT excised from flanking DNA)
3.3’-OH joined to target DNA by strand transfer
reaction (same mechanism as cut-and-paste)
intermediate is double branched DNA molecule
45
46. REPLICATIVE TRANSPOSITION:
4. 3’ ends transposon covalenty linked to target DNA, but
5’ ends still linked to old flanking DNA
5. 2 branches like replication forks, DNA replication proteins
assemble at these forks, 3’-OH serves as primer
6. Replication proceeds through transposon and stops at 2nd
fork 2 copies of transposon flanked by short target site
duplications
• Frequently causes chromosomal inversions and deletions
detrimental to host
46
47. Virus-like retrotransposons and retroviruses:
1. Retrotransposon DNA transcribed into RNA by host
RNAP (transcription starts at promoter within LTR)
2. RNA reverse-transcribed (by RT) RNA:DNA
dsDNA (cDNA)
3. Integrase (transposase) recognizes and binds ends
of cDNA then cleaves few nucleotides off 3’ end of
each strand (just like cleavage step of DNA
transposons)
4. Integrase performs strand transfer reaction to insert
3’ ends into target DNA
5. Gap fill and ligation by host proteins
47
48. PLANT GENOMES ARE RICH IN TRANSPOSONS:
• Snapdragons: size of white
patches related to frequency
of transposition
• Maize color variation due to
chromosome breakage by
transposition
48
50. 5. LINES , SINES
SINES - Short Interspersed Nuclear Elements.
do not have a reverse transcriptase gene but can still transpose, probably by
‘borrowing’ reverse transcriptase enzymes that have been synthesized by other
retroelements.
Eg – human genome Alu
• Length – 280 bp
• Repeats – 700 × 10 to 1000 × 10 (in introns)
LINES – Long Interspersed Nuclear Elements.
It contain a reverse-transcriptase-like gene probably involved in the retro
transposition process
Eg - LINE 1. (Copy no. of 60,000 – 100,000) is a non viral retro element.
50
52. FUNCTIONS OF REPETITIVE DNA
• structural & organizational role in chromosomes.
• protection of genes as histones, rRNA, ribosomal
protein gene.
• At telomere allow linear replication to maintain &
to protect its ends.
52
53. Pathogenenicity islands are discrete genetic loci that
encode factors which make a microbe more virulent
& located on chromoses.
• A host may have more than one pathogenicity island.
• Pathogenicity islands are transferred horizontally,
through plasmids or transposons.
• The addition of a pathogenicity island to a non-
invasive species can make the non-invasive
species pathogenic.
53
54. • These mobile genetic elements may range from 10-
200 kb .
• There are adherence factors, toxins, iron uptake
systems, invasion factors, and secretion systems.
• PAIs are present in the genomes of pathogenic
organisms but absent from the genomes of
nonpathogenic organisms of the same or closely related
species
54
55. • Horizontal gene transfer (HGT) can take place by
transduction, transformation and conjugation.
Plasmids and also larger parts of the genome, like
genomic islands, can be conjugated from one
bacterium to another.
• Pathogenicity islands (PAIs) are a subgroup of
genomic islands. PAIs encode several virulence
factors such as adhesins, toxins, capsules and
siderophore systems and play a major role in the
evolution of pathogenic bacteria such as extra
intestinal e.coli.
• The species E. coli is subdivided into four major
phylogenetic groups (A, B1, B2 and D).
55
56. • PAIs in pathogenic E.
coli were the first
described. It was soon
discovered that
pathogenic bacteria
share many features of
PAIs.
• PAIs carry genes
encoding one or more
virulence factors. They
were first described in
human pathogens but
are also present in
plant pathogens
COMMON FEATURES OF
PATHOGENICITY ISLANDS
56
57. 57
• The average G+C content of bacterial DNA can range
from 25 to 75%. Most pathogenic bacterial species have
G+C contents between 40 and 60%.
• PAI are frequently located adjacent to tRNA genes.
• DR might have served as recognition sites for the
integration of bacteriophages, and their integration resulted
in the duplication of the DR.
• Mutations are cause of instability…integrases,
transposases, and IS elements, have been identified that
contribute to mobilization and as well as to instability.
58. 58
PROTEIN SECRETION SYSTEMS ENCODED
BY PAI
General requirement for pathogenic and nonpathogenic bacteria.
Secreted proteins are required for the assembly of the cell envelope,
metabolism, and defense against, and interaction with, host cells
during pathogenesis.
the presence of an outer membrane in gram-negative bacteria led to
different secretion systems.
Type I Systems
Type II Systems
Type III Systems
Type IV Systems
Type V Systems
59. As of April 2006, PAIDB contains 112 types of PAIs and 889 GenBank
accessions containing either partial or all PAI loci previously reported in the
literature, which are present in 497 strains of pathogenic bacteria.
Bacterial pathogenicity/virulence determinants that can be found in PAIs
include the type III secretion system (e.g. LEE PAI in pathogenic Escherichia
coli), superantigen (e.g. SaPI1 and SaPI2 in Staphylococcus aureus),
colonization factor (e.g. VPI in Vibrio cholerae), iron uptake system (e.g. SHI-2
in Shigella flexneri) and enterotoxin (e.g. espC PAI in E.coli ).
59