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
SOS response was discovered by Miroslav Radman. It's a part of DNA repair system- synthesizes enzymes required for DNA repair. Cellular response to UV damage.
STS stands for sequence tagged site which is short DNA sequence, generally between 100 and 500 bp in length, that is easily recognizable and occurs only once in the chromosome or genome being studied.
SOS response was discovered by Miroslav Radman. It's a part of DNA repair system- synthesizes enzymes required for DNA repair. Cellular response to UV damage.
STS stands for sequence tagged site which is short DNA sequence, generally between 100 and 500 bp in length, that is easily recognizable and occurs only once in the chromosome or genome being studied.
DNA polymerases are a group of enzymes that are used to make copies of DNA templates, essentially used in DNA replication mechanisms. These enzymes make new copies of DNA from existing templates and also function by repairing the synthesized DNA to prevent mutations. DNA polymerase catalyzes the formation of the phosphodiester bond which makes up the backbone of DNA molecules. It uses a magnesium ion in catalytic activity to balance the charge from the phosphate group.
DNA polymerases are a group of enzymes that are used to make copies of DNA templates, essentially used in DNA replication mechanisms. These enzymes make new copies of DNA from existing templates and also function by repairing the synthesized DNA to prevent mutations. DNA polymerase catalyzes the formation of the phosphodiester bond which makes up the backbone of DNA molecules. It uses a magnesium ion in catalytic activity to balance the charge from the phosphate group.
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!!
Genetic Organisation:
All cellular activities are encoded within a cell’s DNA.
The sequence of bases within a DNA molecule represents the genetic information of the cell.
Segments of DNA molecules are called genes, and individual genes contain the instructional code necessary for synthesizing various proteins, enzymes, or stable RNA molecules.
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
What is Genome ?
Types of Genome
Genetic Organization
Genome organization in prokaryotes
BACTERIAL GENOME
Importance of Plasmid
Packaging of DNA
Genome organization in eukaryotes
Chemical composition of chromatin
Nucleosome model
Prokaryotic Genome v/s Eukaryotic Genome
Similar to Genome organization in prokaryotes(molecular biology) (20)
A detailed explanation of cloning strategies which involves isolation of DNA fragments from the sample and introduction in to a vector with restriction enzymes and introduced in to host by different methods and finally screening of the host cells with the recombinants based on protein,nucleicacid and antibiotic assays
control of gene expression by sigma factor and post transcriptional controlIndrajaDoradla
explanation of control of gene expression by sigma factor and decription of sigma factor and detailed explation of post transcriptional control by antisense technology and rna i
description of transgenic animals and production with desired traits using different methods and their applications and their advantages and disadvantages
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
This pdf is about the Schizophrenia.
For more details visit on YouTube; @SELF-EXPLANATORY;
https://www.youtube.com/channel/UCAiarMZDNhe1A3Rnpr_WkzA/videos
Thanks...!
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
What is greenhouse gasses and how many gasses are there to affect the Earth.moosaasad1975
What are greenhouse gasses how they affect the earth and its environment what is the future of the environment and earth how the weather and the climate effects.
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
2. Gene:
It is a unit of heridity which is transferred from a parent to offspring
and held to determine some charecteristic to offspring
Genome:
The entire set of genetic information in an organism
It is encoded in DNA or RNA in case of many viruses
It includes different types of genes they are
Structural genes:
DNA segments that code for some specific RNAs or proteins encode
for mRNAs, tRNAs, SnRNAs
Functional sequences:
The sequences that are regulatory elements such as initiation site,
promoter site, operator site
Non functional sequences:
It includes introns and repetetive sequences
3. Nucleoid
• The nucleoid (meaning nucleus-like) is an irregularly-shaped
region within the cell of a prokaryote that contains all or most of
the genetic material. In contrast to the nucleus of a eukaryotic
cell, it is not surrounded by a nuclear membrane. The genome of
prokaryotic organisms generally is a circular, double-stranded
piece of DNA, of which multiple copies may exist at any time.
The length of a genome varies widely, but is generally at least a
few million base pairs.
4. • The nucleoid can be clearly visualized on an electron micrograph at
high magnification, where it is clearly visible against the cytosol.
Sometimes even strands of what is thought to be DNA are visible. The
nucleoid can also be seen under a light microscope.by staining it with
the Feulgen stain, which specifically stains DNA. The DNA-
intercalating stains DAPI and ethidium bromide are widely used for
fluorescence microscopy of nucleoids.
• Experimental evidence suggests that the nucleoid is largely composed
of about 60% DNA, plus a small amount of RNA and protein. The
latter two constituents are likely to be mainly messenger RNA and the
transcription factor proteins found regulating the bacterial genome.
Proteins helping to maintain the supercoiled structure of the nucleic
acid are known as nucleoid proteins or nucleoid-associated
proteins, and are distinct from histones of eukaryotic nuclei.
5. • The prokaryotic chromosome structure was derived from studies of
E.coli a bacterium that line in human colon in large intestine and
commonly used E.coli in laboratory cloning experiment
• As the DNA of E.coli is larger than the size of the cell it gets problem
for packaging the problem is overcomed by supercoiling of DNA.
6. SUPER COILING
A double helix of DNA undergoes additional twisting in the same
direction or in the opposite direction from the turns in the original
helix.supercoiling results when DNA is subject to same form of
structural strain. A strain is introduced in the DNA to induce
supercoiling
• Positive super coiling twisting in lefthanded fashion
• Negative super coiling twisting in right handed fashion
7. Genomes can be negatively supercoiled or positively supercoiled,
Most bacterial genomes are negatively supercoiled during normal
growth.
Proteins involved in super coiling:
During the 1980s and 1990s, researchers discovered that multiple
proteins act together to fold and condense prokaryotic DNA. In
particular, one protein called HU, which is the most abundant
protein in the nucleoid, works with enzyme called topoisomerase I
to bind DNA and introduce sharp bends in the chromosome,
generating the tension necessary for negative supercoiling. Recent
studies have also shown that other proteins, including integration
host factor (IHF), can bind to specific sequences within the genome
and introduce additional bends . The folded DNA is then organized
into a variety of conformations that are supercoiled and wound
around tetramers of the HU protein
8. Acessing super coiled genes:
• Because there is no nuclear membrane to separate prokaryotic
DNA from the ribosomes within the cytoplasm, transcription and
translation occur simultaneously in these organisms.
• The nucleoid usually appears as an irregularly shaped mass within
the prokaryotic cell, but it becomes spherical when the cell is
treated with chemicals to inhibit transcription or translation.
Moreover, during transcription, small regions of the chromosome
can be seen to project from the nucleoid into the cytoplasm , where
they unwind and associate with ribosomes, thus allowing easy
access by various transcriptional proteins . These projections are
thought to explain the mysterious shape of nucleoids during active
growth. When transcription is inhibited, however, the projections
retreat into the nucleoid, forming spherical shape.
9. The Importance of DNA supercoiling
DNA supercoiling is important for DNA packaging within all cells.
Because the length of DNA can be thousands of times that of a cell,
packaging this genetic material into the cell is difficult .
Supercoiling of DNA reduces the space and allows for much more
DNA to be packaged. In prokaryotes, plectonemic supercoils are
predominant, because of the circular chromosome and relatively
small amount of genetic material.
10. GENOME ORGANIZATION
• Genome organization in prokaryotes takes place by FOLDED
GENOME MODEL
• In folded genome model the large DNA molecule in E.coli
chromosome is organized in to 50 to 100 loops each of which is
negatively supercoiled
• RNA and proteins are both components of folded genome which
can be partially relaxed by treatment with either DNAse or
RNAse
• DNAse removes supercoiling
• RNAse removes folding
11.
12. VARIATIONS IN PROKARYOTIC GENOME
STRUCTURE
• While most prokaryotes, like E. coli, contain a single circular
DNA molecule that makes up their entire genome
Exceptions
Vibrio cholerae cholera - 2 circular chromosomes
one for metabolism and virulence and another for remaining
essential genes
Borrelia burgdorferi Lyme disease - 11 copies of a single
linear chromosome
It cannot supercoil its linear chromosomes into a tight ball within
the nucleoid; rather, these strands are diffused throughout the
cell This organism is transmitted through the bite of deer ticks
Archaea, a taxonomic domain composed of single-celled,
nonbacterial prokaryotes share many similarities with
eukaryotes, can be negatively supercoiled, positively
supercoiled, or not supercoiled at all. It is important to note that
archaeans are the only group of prokaryotes that use eukaryote-
like histones.