BSC-2010 Chapter Notes - Chapter 18: Catabolite Activator Protein, Anabolism, Corepressor
Document Summary
Bacteria respond to environmental change by regulating transcription of gene clusters. Gene expression in bacteria is controlled by genes. Natural selection has favored bacteria that produce only the products needed by that cell. Metabolic pathways must respond to changes in the cell"s environment. A cell can regulate the production of enzymes by feedback inhibition or by gene regulation. Cells control metabolism by regulating enzyme activity or the expression of genes coding for enzymes. In bacteria, genes are often clustered into operons, with one promoter serving several adjacent genes. Operons- a cluster of functionally regulated genes that can be controlled by a single on-off switch. The switch is a part of dna called an operator which is usually located in the promoter. Promoter- a specific nucleotide sequence in the dna of a gene that binds. Rna polymerase, positioning it to start transcribing rna at the appropriate place. Both repressible and inducible operons are negative gene regulation.
