Bacterial Metabolism Questions

1995

"Give an account of the role of sensor kinase systems in the regulation of
nitrogen metabolism by bacteria.  What features do the systems you
describe have in common with the response of bacteria to other
environmental challenges?"

1996

"Give an account of the structure, and other features of interest, of
bacterial nitrogenase.  How is synthesis of the enzyme regulated in
free-living bacteria?"

"Recent research has shown that some bacterial species are able to sense
their population density.  Describe the mechanisms involved and the role
of quorum sensing."

1997

Either

"Many bacterial species are able to grow in anaerobic and aerobic
environments.  How are changes in oxygen concentration sensed and how does
this affect gene regulation?"

Or

"To respond to an effector gradient, bacteria must be able both to
terminate the sensory signal and adapt to the current
environment.  Describe the mechanisms for doing this."

"Compare and contrast the nitrogen fixation and denitrification reactions
of the nitrogen cycle."

1998

"Compare the molecular mechanisms involved in biasing a swimming E.coli
cell towards an attractant with those involved in controlling expression
of pathways in anaerobic metabolism."

"Describe the enzymology of nitrogen fixation to ammonia.  Explain how and
why the expression of this nitrogen fixation system is regulated."

"Giving specific examples, explain what is meant by 'quorum' or cell
density-dependent signalling in bacteria."

1999

"Describe the mechanisms that allow either plants or bacteria to acquire,
assimilate and retain nitrogen.  Include a discussion of the
compartmentation of the relevant pathways."

"Many pathogenic bacteria express their pathogenic phenotype only when in
specific locations within a host.  Using specific examples, describe how
the organisms senses that it is within a host, and the responses to this
sensory input."

2000

"In prokaryotes, a large number of environmental changes are sensed by
phospho-relay pathways.  Describe two of these pathways, and discuss why
cross-talk does not occur."

"Some species of bacteria can grow under both aerobic and anaerobic
conditions.  Discuss with examples what is entailed in this switch."