BIOLOGY 1A03 Lecture Notes - Lecture 2: Lactose Permease, Adenylyl Cyclase, Tetrameric Protein

• School: McMaster University
• Department: Biology
• Course: BIOLOGY 1A03
• Professor: Alastair Tracey Rosa Da Silva

Document Summary

Environmental cues: changes in glucose levels, presence of lactose. B-galactosidase and lactose permease proteins are not detectable in e coli until there is no glucose present. B-galactosidase and lactose permease are produced in response to environmental cues and allows for the effective digestion of lactose. Lactose permease is a transport protein that sits in the bacterial cell membrane and allows for transport of lactose into the bacterial cells. B-galactosidase protein is a cytoplasmically situated bacterial enzyme that cleaves the imported lactose into glucose and galactose. Key advantage of prokaryotic genome: groups of related gene with similar functions can often be found clustered together into operons; leads to the ability to control the transcription of the whole gene cluster as one unit; b- Consists of a promoter, an operator (on/off switch), and the coordinated gene cluster whose products will function in a common pathway/cellular response.