BIOLOGY 1A03 Lecture Notes - Lecture 12: Tetrameric Protein, Adenylyl Cyclase, Lac Operon

• School: McMaster University
• Department: Biology
• Course: BIOLOGY 1A03
• Professor: Kim Dej

Document Summary

Bio 1a03 lecture 12 prokaryotic transcription regulation: as e. coli cells transition from glucose to lactose, there is an increase in the amount of b- galactosidase and lactose permease proteins. E. coli cells use glucose as a primary energy source: these proteins are produced in response to deleted glucose reserves. The lactose permease is a transport protein that uptakes lactose into cells. The b-galactosidase protein is the enzyme that cleaves the imported lactose into glucose and galactose. These genes are in an operon, which allows then to be easily regulated. In 1961, francois jacob and jacques monod discovered this type of gene control. These genes care organized into transcriptional units along the bacterial chromosome: these gene clusters are coordinately controlled by an on-off switch that can control these clustered genes. Lacy gene codes for a lactose permease transport protein which imports lactose into the cell. The lacz gene codes for b-galactosidase which breaks down lactose into glucose and galactose.