Abstract
Bacteria often sequentially utilize coexisting carbohydrates in environment and firstly select the one (frequently glucose) easiest to metabolize. This phenomenon is known as carbon catabolite repression (CCR). In existing Chinese teaching materials of molecular biology and related courses, unclear or even wrong interpretations are given about CCR mechanism. A large number of studies have shown that rather than the existence of intracellular glucose, CCR is mainly caused by the glucose transport process coupling with glucose phosphorylation via the phosphoenolpyruvate: carbohydrate phosphotransferase system PTS. The transport process leads to accumulation of dephosphorylated form of EAGlc.This form of EAGlc can bind the membrane-localized LacY protein to block the uptake of lactose inducer. cAMP functions in activation of key genes involved in PTS system to strengthen the role of inducer exclusion. In addition, dephosphorylated form of EBGlc and Yee bind global transcription repressor Mlc to ensure the expression of key genes involved in the PTS system. This review summarizes the current advancement in mechanism of Escherichia coli carbon catabolite repression.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
