Deck 3 Flashcards
When E. coli senses an attractant it regulates the switching between what and what?
Run and tumble
Causes zigzag like pattern
What is a brief description of the run cycle for E. coli?
Increased MCPs binding to attractant inhibits CheA phosphorylation
CCW rotation continues
What is a brief description of the tumble cycle of E. coli?
Decreased attractant level causes CheA to autophosphorylate
Flagella changes to CW motion
What is quorum sensing?
Cell to cell communication in a density dependent manner to coordinate their behavior
In quorum sensing when a what reaches a threshold level, it will induce the expression of what?
Autoinducer
Target genes
In quorum sensing the autoinducer (AHL) is activated by what?
The regulator LuxR
Quorum sensing has regulation at both what and what levels?
Posttranslational (LuxR)
Transcription (lux operon)
In quorum sensing AHL increases when what increases?
Cell density
The lac operon ensures a balanced breakdown and uptake of what?
Lactose
(T/F) The lacl, which encodes the repressor, is part of the operon
False, it has its own separate promoter
(T/F) lac operon genes are expressed when lactose is the ONLY carbon source
True!
What happens to lac operon in the following conditions:
No lactose
Lactose, no glucose
Lactose and glucose
Inhibited
Active (high [cAMP], CAP binds)
Inactive (low [cAMP], CAP does not bind)
What is the relationship between glucose and cAMP levels?
Inverse, when glucose is high, cAMP is low
What is the name of the phase where the bacteria goes from the animal host back to the mosquito?
Gametocyte
What phase of bacteria infects the RBC and rapidly reproduces, killing the RBC
Merozoite
