BIOL 261 Chapter 11: Chap 11
Document Summary
Chapter 11: regulation of gene expression in bacteria and their viruses. Bacteria + complex organisms have in common the need to regulate expression of genes. Bacteria obtain important compounds swim in a sea of potential nutrients can either acquire compound needed from environment or synthesize them by enzymatic pathways. Synthesizing these compounds also requires expending energy + cellular resources to produce the necessary enzymes for these pathways. Given choice bacteria will take nutrients from environment. Natural selection favours efficiency + selects against the waste of resources. Bacteria have evolved regulatory systems that couple the expression of gene products to sensor systems that detect relevant compounds in bacterium"s local environment. Regulation of enzymes taking part in sugar metabolism example. Sugar molecules broken down to provide energy or can be used as building blocks for a range of organic compounds. Different types of sugar = lactose, glucose, galactose, xylose. Different important protein required to process each of the sugars.