15-gene expression.ppt
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This document summarizes different mechanisms of transcriptional regulation in prokaryotes: - Gene expression is controlled by promoter and operator regions located near structural genes organized into operons. Transcription can be regulated positively by activators or negatively by repressors binding the operator. - Repression involves a repressor protein binding the operator and blocking transcription until an inducer molecule inactivates the repressor. Induction allows transcription in the presence of an inducer like allolactose. - Attenuation regulates transcription based on whether a ribosome stalls while translating the leader peptide due to lack of a tRNA, allowing transcription, or whether it terminates, forming a hairpin to terminate transcription.
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Gene regulation operon
Gene expression in bacteria is often regulated through operons. The lac operon in E. coli consists of structural genes that encode proteins for lactose metabolism regulated by the lac repressor. In the presence of lactose and absence of glucose, cAMP levels rise and activate the catabolite activator protein (CAP), allowing transcription. The trp operon encodes tryptophan synthesis and is regulated by the trp repressor as well as attenuation, where ribosome movement influences RNA structure and termination. Operons demonstrate how prokaryotes efficiently coordinate gene expression through transcriptional control mechanisms.
biochemistry Regulation of gene expression
The document describes regulation of gene expression in prokaryotic and eukaryotic cells. In prokaryotes, gene expression is regulated through operons, clusters of genes that are coordinately controlled. The lac and trp operons in E. coli are discussed as examples, with the lac operon being inducible and the trp operon being repressible. In eukaryotes, gene expression can be regulated at many stages including chromatin modifications, transcription, RNA processing, translation and protein modification. This allows for cell specialization and differential gene expression with the same genome.
Gene regulation and operon concept2.pptx
Gene regulation in prokaryotes occurs through operons, clusters of genes that are expressed together. The lac and trp operons are examples of inducible and repressible operons, respectively. The lac operon is induced by the presence of lactose and involves both positive and negative control. It is negatively controlled by the lac repressor binding to the operator, but activated by the catabolite activator protein. The trp operon is repressed by the binding of tryptophan to the trp repressor, preventing transcription. It also uses attenuation, where mRNA folding terminates transcription at high tryptophan levels. Operons regulate metabolic pathways through induction or repression in response to environmental conditions.
Gene expression in prokaryotes
The document summarizes gene expression and regulation in prokaryotes. It discusses how prokaryotes transcribe genes only when needed to increase efficiency. Gene expression is regulated primarily at the transcription level through operons like the lac and trp operons. The lac operon is induced by lactose and inhibited by glucose, while the trp operon is repressed by tryptophan to control biosynthesis. Both operons use repressor proteins that bind DNA in response to metabolites to regulate transcription.
Gene expression in prokaryotes
The document summarizes gene expression in prokaryotes. It discusses how prokaryotic genes are organized into operons that are regulated coordinately. It provides examples of the lac and trp operons. The lac operon encodes enzymes for lactose metabolism and is induced by lactose. The trp operon encodes enzymes for tryptophan synthesis and is repressed by tryptophan through binding of the trp repressor to the operator. Both operons utilize repressors and operators to control transcription in response to substrates or end products.
Trp operon
The tryptophan operon is a negatively induced operon in E. coli that is regulated by the presence of tryptophan. It contains structural genes that code for enzymes involved in tryptophan biosynthesis. In low tryptophan conditions, transcriptional attenuation allows the transcription of the structural genes. In high tryptophan conditions, transcriptional attenuation terminates transcription before the structural genes. The mechanism involves the formation of alternative stem loop RNA structures and stalling of ribosomes in the leader region.
Gene expression in_prokaryotes
can you exchange gene expression in eukaryotes.If not never mind,let it be next time.
Dr. Anil Batta
Lac operon sohil
The document discusses various mechanisms of gene expression and regulation in prokaryotes and eukaryotes. It explains that gene expression involves the transcription of DNA into mRNA and the translation of mRNA into protein. In prokaryotes, genes may be organized into operons and regulated through repression and induction. The lactose and tryptophan operons are discussed as examples. Eukaryotes have additional complexities in gene expression including RNA processing, alternative splicing, and transport of mRNA. Gene expression is regulated at transcriptional, post-transcriptional, translational, and post-translational levels.
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Gene regulation operon
Gene expression in bacteria is often regulated through operons. The lac operon in E. coli consists of structural genes that encode proteins for lactose metabolism regulated by the lac repressor. In the presence of lactose and absence of glucose, cAMP levels rise and activate the catabolite activator protein (CAP), allowing transcription. The trp operon encodes tryptophan synthesis and is regulated by the trp repressor as well as attenuation, where ribosome movement influences RNA structure and termination. Operons demonstrate how prokaryotes efficiently coordinate gene expression through transcriptional control mechanisms.
biochemistry Regulation of gene expression
The document describes regulation of gene expression in prokaryotic and eukaryotic cells. In prokaryotes, gene expression is regulated through operons, clusters of genes that are coordinately controlled. The lac and trp operons in E. coli are discussed as examples, with the lac operon being inducible and the trp operon being repressible. In eukaryotes, gene expression can be regulated at many stages including chromatin modifications, transcription, RNA processing, translation and protein modification. This allows for cell specialization and differential gene expression with the same genome.
Gene regulation and operon concept2.pptx
Gene regulation in prokaryotes occurs through operons, clusters of genes that are expressed together. The lac and trp operons are examples of inducible and repressible operons, respectively. The lac operon is induced by the presence of lactose and involves both positive and negative control. It is negatively controlled by the lac repressor binding to the operator, but activated by the catabolite activator protein. The trp operon is repressed by the binding of tryptophan to the trp repressor, preventing transcription. It also uses attenuation, where mRNA folding terminates transcription at high tryptophan levels. Operons regulate metabolic pathways through induction or repression in response to environmental conditions.
Gene expression in prokaryotes
The document summarizes gene expression and regulation in prokaryotes. It discusses how prokaryotes transcribe genes only when needed to increase efficiency. Gene expression is regulated primarily at the transcription level through operons like the lac and trp operons. The lac operon is induced by lactose and inhibited by glucose, while the trp operon is repressed by tryptophan to control biosynthesis. Both operons use repressor proteins that bind DNA in response to metabolites to regulate transcription.
Gene expression in prokaryotes
The document summarizes gene expression in prokaryotes. It discusses how prokaryotic genes are organized into operons that are regulated coordinately. It provides examples of the lac and trp operons. The lac operon encodes enzymes for lactose metabolism and is induced by lactose. The trp operon encodes enzymes for tryptophan synthesis and is repressed by tryptophan through binding of the trp repressor to the operator. Both operons utilize repressors and operators to control transcription in response to substrates or end products.
Trp operon
The tryptophan operon is a negatively induced operon in E. coli that is regulated by the presence of tryptophan. It contains structural genes that code for enzymes involved in tryptophan biosynthesis. In low tryptophan conditions, transcriptional attenuation allows the transcription of the structural genes. In high tryptophan conditions, transcriptional attenuation terminates transcription before the structural genes. The mechanism involves the formation of alternative stem loop RNA structures and stalling of ribosomes in the leader region.
Gene expression in_prokaryotes
can you exchange gene expression in eukaryotes.If not never mind,let it be next time.
Dr. Anil Batta
Lac operon sohil
The document discusses various mechanisms of gene expression and regulation in prokaryotes and eukaryotes. It explains that gene expression involves the transcription of DNA into mRNA and the translation of mRNA into protein. In prokaryotes, genes may be organized into operons and regulated through repression and induction. The lactose and tryptophan operons are discussed as examples. Eukaryotes have additional complexities in gene expression including RNA processing, alternative splicing, and transport of mRNA. Gene expression is regulated at transcriptional, post-transcriptional, translational, and post-translational levels.
Lac operon (1)
The regulation of gene expression is critical for all organisms. There are two main types of genes - constitutive genes that are always "on" and non-constitutive or luxury genes that are regulated. Gene regulation involves turning genes on and off through transcriptional and translational control. Key elements that regulate genes include regulatory genes, structural genes, and regulatory elements in DNA that control transcription. Regulation can occur at the level of DNA, transcription, mRNA processing, translation, and post-translation. The lac operon in E. coli is an example of negative inducible gene regulation involving a repressor, operator, and inducer to control lactose metabolism genes.
Gene regulation
Imagine a situation when a cell starts producing enzymes required for metabolism and those required for cell death (apoptosis) at the same time. The cell will be in a confused state and will not know which function to perform first. The needs of the body keep changing with time and cell has to tune itself to perform the desired set of activities. Gene regulation helps a unicellular organism to adapt well to the environment.
Lac Operon
The document summarizes gene regulation in prokaryotes and eukaryotes. In prokaryotes, genes are organized into operons that are regulated by repressor or inducible systems like the tryptophan and lactose operons. The tryptophan operon is turned off by a repressor when tryptophan levels are high. The lactose operon is induced when lactose is present and glucose levels are low. In eukaryotes, gene expression is controlled through chromatin structure, pre-transcriptional and post-transcriptional regulation involving transcription factors and RNA processing, and pre-translational and post-translational regulation involving translation initiation, protein processing and degradation.
Regulation of gene expression b,pharm
Regulation of gene expression allows cells to control which genes are expressed and when. In prokaryotes like E. coli, genes are often organized into operons, clusters of genes that are co-transcribed. The lac and tryptophan operons are examples that are regulated by repressor proteins - the lac operon is induced by lactose binding to the repressor, while the tryptophan operon is derepressed in the absence of tryptophan. Eukaryotes like humans have more complex gene expression involving different cell types each expressing different gene sets.
Regulation of gene expression in prokaryotes and viruses
Regulation of gene expression in prokaryotes and viruses includes gene expression mechanism of prokaryotes such as lac operon ,trp operon, feedback inhibition, types of temporal response, positive and negative gene regulation. It also includes mechanisms such as reverse transcriptase in viruses.
Gene regulation in Prokaryotes.pptx
The document discusses gene regulation in prokaryotes, focusing on the lac operon in E. coli. It describes how the lac operon is regulated by a repressor protein, lactose as an inducer, and CRP/cAMP as a positive regulator. In the absence of lactose, the repressor binds to the operator region and prevents transcription. In the presence of lactose, it binds to the inducer and detaches from the operator, allowing transcription. CRP/cAMP activate transcription when glucose is low. The lac operon thus demonstrates negative and positive, inducible and repressible regulation depending on environmental conditions.
Operon Concept
The document discusses the concept of operons in prokaryotes. It defines an operon as a coordinated group of genes that are transcribed together to regulate a metabolic pathway. The key components of an operon are structural genes, an operator, promoter and regulator gene. Operons can be regulated by repressors or activators binding to the operator, which determines if transcription occurs. Examples discussed include the lac and tryptophan operons, which are regulated by negative and positive control, respectively. Transcriptional attenuation is also described as another level of gene regulation. In conclusion, precise regulation of gene expression is essential for organisms to produce the correct phenotypes under different conditions.
Prokaryotic gene regulation
There are two main mechanisms of transcriptional control of gene expression in prokaryotes: 1) Operons, where genes involved in a metabolic pathway are clustered under common regulatory sequences and proteins, allowing synchronized expression. 2) Cascades of gene expression, where expression of one gene set can activate expression of another gene set. The lactose and tryptophan operons are examples that demonstrate negative and positive regulation of gene expression through repressors, inducers, and feedback loops in response to environmental conditions.
Regulation of gene expression in Prokaryotes (Lac Operon).pptx by Muhammad An...
1. The lac operon regulates the expression of genes involved in lactose catabolism in prokaryotes in response to the presence of lactose or glucose.
2. It consists of structural genes that encode enzymes for lactose breakdown and a regulatory gene that produces a repressor protein.
3. In the absence of lactose, the repressor binds to the operator region and prevents transcription of the structural genes. However, in the presence of lactose, it binds to lactose instead, allowing transcription.
a.pptx
The document discusses several key concepts in gene regulation:
1. Genes can be constitutively expressed or regulated in response to cellular needs through induction or repression.
2. RNA polymerase binding to promoters is a major target of regulation by transcription factors that enhance or inhibit this interaction.
3. Small molecules called effectors can regulate activators and repressors to control transcription.
4. Many examples are given of specific gene regulation mechanisms in bacteria like the lac and trp operons.
Regulation of Gene Expression
Gene regulation is how a cell controls which genes, out of the many genes in its genome, are "turned on" (expressed). Thanks to gene regulation, each cell type in your body has a different set of active genes – despite the fact that almost all the cells of your body contain the exact same DNA. These different patterns of gene expression cause your various cell types to have different sets of proteins, making each cell type uniquely specialized to do its job. [Source: https://www.khanacademy.org/science/biology/gene-regulation/gene-regulation-in-eukaryotes/a/overview-of-eukaryotic-gene-regulation]
Trp Operon.pptx
The trp operon controls the biosynthesis of tryptophan in E. coli. It contains 5 genes that encode enzymes for tryptophan production. The operon uses attenuation to regulate expression based on tryptophan levels. When tryptophan is low, transcription proceeds through the leader sequence. When tryptophan is high, translation is rapid and a stem loop structure forms, terminating transcription. The trp operon is a repressible system, where the effector molecule allows the repressor to bind the operator and shut down expression.
2. Tryptophan operon.ppt
This document summarizes two bacterial operons - the arabinose (ara) operon and the tryptophan (trp) operon.
The ara operon contains three genes involved in arabinose metabolism and is regulated by the AraC protein. AraC can act as either a negative or positive regulator depending on the presence of arabinose. The trp operon contains genes for tryptophan biosynthesis and is regulated by the TrpR repressor protein and attenuation. Transcription is repressed when tryptophan is present but induced when tryptophan levels are low. Both operons demonstrate inducible and repressible regulation depending on substrate availability.
Trp operon
The trp operon contains a cluster of genes involved in tryptophan biosynthesis that are under the control of a single promoter. It was the first repressible operon discovered in E. coli in 1953. The trp operon contains structural genes that encode enzymes for tryptophan synthesis, as well as a promoter, operator, and regulatory genes. Tryptophan acts as an effector molecule that binds to the repressor protein, increasing its affinity for the operator sequence and repressing transcription when tryptophan is present. The trp operon is also regulated by transcriptional attenuation, where tryptophan levels affect the formation of termination or anti-termination hairpin loops in the mRNA.
Regulation of gene expression and genetics.ppt
Gene expression is regulated at multiple levels in eukaryotes and prokaryotes. In prokaryotes, gene expression is mainly controlled at the transcriptional level through the use of operons. Operons include a promoter, operator, and structural genes. In eukaryotes, gene expression is regulated at the transcriptional level as well as post-transcriptionally through RNA processing, transport, translation, and degradation. This allows for more complex regulation in eukaryotes compared to prokaryotes.
Gene regulation
This document summarizes transcriptional and post-transcriptional gene regulation. It discusses how gene expression can be regulated at the transcriptional and post-transcriptional levels in both prokaryotes and eukaryotes. In prokaryotes, operons like the lac and trp operons are used to regulate transcription through inducible/repressible systems. In eukaryotes, transcription factors bind to regulatory elements to control transcription initiation, and post-transcriptional modifications like RNA processing and histone/DNA modifications regulate gene expression. Regulatory mechanisms allow organisms to precisely control gene expression in response to environmental conditions.
Operon
1. The document discusses the lac operon and tryptophan (trp) operon in prokaryotes. The lac operon regulates genes for lactose metabolism in E. coli and was discovered by Jacob and Monod in 1961.
2. The trp operon regulates genes for tryptophan biosynthesis and contains 5 structural genes. It is regulated by a trp repressor protein and uses attenuation to fine tune expression based on tryptophan levels.
3. Both operons use repressor proteins and operator sites to control transcription in response to specific metabolites - lactose for the lac operon and tryptophan for the trp operon. Repression allows transcription when
gene expression in prokaryotes.pptx
Gene expression in prokaryotes is often controlled through operons, which group functionally related genes together so they can be coregulated. A classic example is the lac operon in E. coli, which contains genes needed for lactose utilization. The lac operon is regulated by a repressor protein that binds to the operator region and blocks transcription when lactose is absent. In the presence of lactose, it binds the inducer and falls off the operator, allowing transcription. Similarly, the trp operon contains genes for tryptophan synthesis and is negatively regulated by a repressor.
Lecture notes_Tryptophan operon and its regulation.pdf
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The regulation of gene expression is critical for all organisms. There are two main types of genes - constitutive genes that are always "on" and non-constitutive or luxury genes that are regulated. Gene regulation involves turning genes on and off through transcriptional and translational control. Key elements that regulate genes include regulatory genes, structural genes, and regulatory elements in DNA that control transcription. Regulation can occur at the level of DNA, transcription, mRNA processing, translation, and post-translation. The lac operon in E. coli is an example of negative inducible gene regulation involving a repressor, operator, and inducer to control lactose metabolism genes.
Gene regulation
Imagine a situation when a cell starts producing enzymes required for metabolism and those required for cell death (apoptosis) at the same time. The cell will be in a confused state and will not know which function to perform first. The needs of the body keep changing with time and cell has to tune itself to perform the desired set of activities. Gene regulation helps a unicellular organism to adapt well to the environment.
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The document summarizes gene regulation in prokaryotes and eukaryotes. In prokaryotes, genes are organized into operons that are regulated by repressor or inducible systems like the tryptophan and lactose operons. The tryptophan operon is turned off by a repressor when tryptophan levels are high. The lactose operon is induced when lactose is present and glucose levels are low. In eukaryotes, gene expression is controlled through chromatin structure, pre-transcriptional and post-transcriptional regulation involving transcription factors and RNA processing, and pre-translational and post-translational regulation involving translation initiation, protein processing and degradation.
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Regulation of gene expression allows cells to control which genes are expressed and when. In prokaryotes like E. coli, genes are often organized into operons, clusters of genes that are co-transcribed. The lac and tryptophan operons are examples that are regulated by repressor proteins - the lac operon is induced by lactose binding to the repressor, while the tryptophan operon is derepressed in the absence of tryptophan. Eukaryotes like humans have more complex gene expression involving different cell types each expressing different gene sets.
Regulation of gene expression in prokaryotes and viruses
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The document discusses gene regulation in prokaryotes, focusing on the lac operon in E. coli. It describes how the lac operon is regulated by a repressor protein, lactose as an inducer, and CRP/cAMP as a positive regulator. In the absence of lactose, the repressor binds to the operator region and prevents transcription. In the presence of lactose, it binds to the inducer and detaches from the operator, allowing transcription. CRP/cAMP activate transcription when glucose is low. The lac operon thus demonstrates negative and positive, inducible and repressible regulation depending on environmental conditions.
Operon Concept
The document discusses the concept of operons in prokaryotes. It defines an operon as a coordinated group of genes that are transcribed together to regulate a metabolic pathway. The key components of an operon are structural genes, an operator, promoter and regulator gene. Operons can be regulated by repressors or activators binding to the operator, which determines if transcription occurs. Examples discussed include the lac and tryptophan operons, which are regulated by negative and positive control, respectively. Transcriptional attenuation is also described as another level of gene regulation. In conclusion, precise regulation of gene expression is essential for organisms to produce the correct phenotypes under different conditions.
Prokaryotic gene regulation
There are two main mechanisms of transcriptional control of gene expression in prokaryotes: 1) Operons, where genes involved in a metabolic pathway are clustered under common regulatory sequences and proteins, allowing synchronized expression. 2) Cascades of gene expression, where expression of one gene set can activate expression of another gene set. The lactose and tryptophan operons are examples that demonstrate negative and positive regulation of gene expression through repressors, inducers, and feedback loops in response to environmental conditions.
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1. The lac operon regulates the expression of genes involved in lactose catabolism in prokaryotes in response to the presence of lactose or glucose.
2. It consists of structural genes that encode enzymes for lactose breakdown and a regulatory gene that produces a repressor protein.
3. In the absence of lactose, the repressor binds to the operator region and prevents transcription of the structural genes. However, in the presence of lactose, it binds to lactose instead, allowing transcription.
a.pptx
The document discusses several key concepts in gene regulation:
1. Genes can be constitutively expressed or regulated in response to cellular needs through induction or repression.
2. RNA polymerase binding to promoters is a major target of regulation by transcription factors that enhance or inhibit this interaction.
3. Small molecules called effectors can regulate activators and repressors to control transcription.
4. Many examples are given of specific gene regulation mechanisms in bacteria like the lac and trp operons.
Regulation of Gene Expression
Gene regulation is how a cell controls which genes, out of the many genes in its genome, are "turned on" (expressed). Thanks to gene regulation, each cell type in your body has a different set of active genes – despite the fact that almost all the cells of your body contain the exact same DNA. These different patterns of gene expression cause your various cell types to have different sets of proteins, making each cell type uniquely specialized to do its job. [Source: https://www.khanacademy.org/science/biology/gene-regulation/gene-regulation-in-eukaryotes/a/overview-of-eukaryotic-gene-regulation]
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The trp operon controls the biosynthesis of tryptophan in E. coli. It contains 5 genes that encode enzymes for tryptophan production. The operon uses attenuation to regulate expression based on tryptophan levels. When tryptophan is low, transcription proceeds through the leader sequence. When tryptophan is high, translation is rapid and a stem loop structure forms, terminating transcription. The trp operon is a repressible system, where the effector molecule allows the repressor to bind the operator and shut down expression.
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This document summarizes two bacterial operons - the arabinose (ara) operon and the tryptophan (trp) operon.
The ara operon contains three genes involved in arabinose metabolism and is regulated by the AraC protein. AraC can act as either a negative or positive regulator depending on the presence of arabinose. The trp operon contains genes for tryptophan biosynthesis and is regulated by the TrpR repressor protein and attenuation. Transcription is repressed when tryptophan is present but induced when tryptophan levels are low. Both operons demonstrate inducible and repressible regulation depending on substrate availability.
Trp operon
The trp operon contains a cluster of genes involved in tryptophan biosynthesis that are under the control of a single promoter. It was the first repressible operon discovered in E. coli in 1953. The trp operon contains structural genes that encode enzymes for tryptophan synthesis, as well as a promoter, operator, and regulatory genes. Tryptophan acts as an effector molecule that binds to the repressor protein, increasing its affinity for the operator sequence and repressing transcription when tryptophan is present. The trp operon is also regulated by transcriptional attenuation, where tryptophan levels affect the formation of termination or anti-termination hairpin loops in the mRNA.
Regulation of gene expression and genetics.ppt
Gene expression is regulated at multiple levels in eukaryotes and prokaryotes. In prokaryotes, gene expression is mainly controlled at the transcriptional level through the use of operons. Operons include a promoter, operator, and structural genes. In eukaryotes, gene expression is regulated at the transcriptional level as well as post-transcriptionally through RNA processing, transport, translation, and degradation. This allows for more complex regulation in eukaryotes compared to prokaryotes.
Gene regulation
This document summarizes transcriptional and post-transcriptional gene regulation. It discusses how gene expression can be regulated at the transcriptional and post-transcriptional levels in both prokaryotes and eukaryotes. In prokaryotes, operons like the lac and trp operons are used to regulate transcription through inducible/repressible systems. In eukaryotes, transcription factors bind to regulatory elements to control transcription initiation, and post-transcriptional modifications like RNA processing and histone/DNA modifications regulate gene expression. Regulatory mechanisms allow organisms to precisely control gene expression in response to environmental conditions.
Operon
1. The document discusses the lac operon and tryptophan (trp) operon in prokaryotes. The lac operon regulates genes for lactose metabolism in E. coli and was discovered by Jacob and Monod in 1961.
2. The trp operon regulates genes for tryptophan biosynthesis and contains 5 structural genes. It is regulated by a trp repressor protein and uses attenuation to fine tune expression based on tryptophan levels.
3. Both operons use repressor proteins and operator sites to control transcription in response to specific metabolites - lactose for the lac operon and tryptophan for the trp operon. Repression allows transcription when
gene expression in prokaryotes.pptx
Gene expression in prokaryotes is often controlled through operons, which group functionally related genes together so they can be coregulated. A classic example is the lac operon in E. coli, which contains genes needed for lactose utilization. The lac operon is regulated by a repressor protein that binds to the operator region and blocks transcription when lactose is absent. In the presence of lactose, it binds the inducer and falls off the operator, allowing transcription. Similarly, the trp operon contains genes for tryptophan synthesis and is negatively regulated by a repressor.
Lecture notes_Tryptophan operon and its regulation.pdf
Lecture notes_Tryptophan operon and its regulation
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Heat shock proteins (HSPs) help other proteins properly fold and function. HSP90 and HSP70 are molecular chaperones that work sequentially to fold proteins in the cytoplasm. Misfolded proteins can cause disease. HSP90 helps buffer hidden genetic variations but under stress these variations are expressed and can lead to morphological changes. HSP90 is highly conserved across species and plays a role in evolution by allowing traits to change in response to stress. Current research studies HSP90 to better understand protein misfolding diseases.
enzymes.ppt
1. Enzymes are biological catalysts that lower the activation energy of reactions and increase reaction rates. They are often proteins that contain cofactors.
2. Enzymes are classified based on the type of reaction they catalyze, such as oxidation-reduction, hydrolysis, or transfer of chemical groups. Common enzyme names end in "-ase".
3. The lock and key model describes how enzymes bind specifically to substrates in their active sites to form enzyme-substrate complexes. In the induced fit model, the enzyme structure changes to better fit the substrate.
Classification_of_protein_structure.ppt
Protein structures are classified to generate overviews of structure types and detect evolutionary relationships. Major classification schemes include SCOP, CATH, and FSSP. SCOP classifies proteins into classes, folds, superfamilies, and families based on structural and sequence similarities. CATH also uses a hierarchical system of classes, architectures, topologies, and superfamilies. FSSP provides fully automated and updated structural alignments and classifications.
chapter6.ppt
This document discusses proteins from a chemist's perspective. It describes how proteins are made of amino acids, with 20 standard types but only 9 being essential. The unique side groups of each amino acid determine their individual properties. Protein structure and function depend on the specific amino acid sequence. Amino acids are linked through peptide bonds to form proteins. The document also covers protein digestion and roles of proteins in the body.
class_L02.ppt
This document discusses protein structure and synthesis. It begins by describing the primary, secondary, tertiary, and quaternary structures of proteins. This includes the structures of alpha helices, beta sheets, turns, and domains. It then discusses protein translation, noting that proteins begin folding as they emerge from the ribosome in a co-translational manner. The final section discusses protein folding and some of the challenges of the folding process.
centoni (2).ppt
The document discusses heat shock proteins (Hsps), Hsp90 inhibitors, and protein degradation. It provides background on protein degradation mechanisms and heat shock proteins. Hsp90 plays a key role in cancer cell survival by regulating oncogenic signaling proteins. Hsp90 inhibitors like geldanamycin and 17-AAG bind Hsp90's ATP binding site, altering its function and inducing degradation of client proteins, stopping cancer cell growth. The paper found that tumor Hsp90 exclusively exists in active multichaperone complexes, conferring higher binding affinity for 17-AAG compared to normal cell Hsp90. This activated conformation in tumor cells represents a unique drug target.
Background.ppt
This document summarizes protein therapeutics and provides a pharmacological classification. It notes that the human genome contains 25,000-40,000 genes that can undergo alternative splicing and post-translational modifications, resulting in a very high number of functionally distinct proteins. Protein therapeutics are classified into 4 groups based on their function: group I includes proteins with enzymatic or regulatory activity, group II targets specific molecules or organisms, group III are protein vaccines, and group IV are protein diagnostics. The document outlines some advantages of protein therapeutics but also challenges including solubility, immune response, stability, and costs.
2005_lecture_01.ppt
1. Proteins are made up of amino acids and take on specific three-dimensional structures that dictate their function. Determining a protein's structure is important for understanding its role in biological processes.
2. There are several methods for determining and predicting protein structure, including X-ray crystallography, NMR, and computational methods like homology modeling or ab initio structure prediction.
3. Protein structure is hierarchical, ranging from secondary structure like alpha helices and beta sheets to the overall fold classified in databases like SCOP and CATH. Predicting secondary structure is easier than predicting a protein's full three-dimensional structure.
Amino_Acids_and_Proteins.ppt
Amino acids are organic compounds that contain an amino group and a carboxyl group. There are 20 different amino acids that serve as the building blocks of proteins. Amino acids link together through peptide bonds to form polypeptide chains that fold into complex three-dimensional protein structures. Proteins serve essential functions and 10 of the 20 amino acids must be obtained through diet as humans cannot synthesize them. Common protein tests identify the presence of proteins using reactions that detect peptide bonds, amino acid side chains, or disulfide bridges.
142 proteinsoutline.ppt
- Proteins are made up of amino acids, which are the building blocks. There are 20 different amino acids, some are essential and must be obtained through diet.
- The specific sequence of amino acids determines the 3D shape of a protein and its function. Denaturation occurs when proteins lose their shape due to heat, acid, etc.
- Proteins serve many important functions in the body including structure, enzymes, transport, hormones, antibodies, and more. An inadequate intake can result in the body breaking down its own proteins to obtain energy.
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- 1. Regulation of Gene Expression • Chromosomal Map begins at OriC; units of minutes. – Only structural genes for enzymes are shown here. – Their control regions (promoter and operator) determine transcription. – The complete organizational unit is an operon. • Transcriptional regulation: – Negative Control by Repressors • Repression • Induction – Positive Control by Activators – Attenuation (involves translation)
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