ISOLATION OF A COMPONENT OF THE BACTERIAL EXPORT PATHWAY

Project: Research project

Description

Cells have multiple compartments, each with a unique set of
proteins which support specialized functions. These
compartments are separated by lipid-rich membranes. How does
a cell sort newly made proteins to their correct compartments
and transport them across the appropriate membranes? To
address this question, mutations in the export pathway of E. coli
have been isolated. Cells bearing these mutations exhibit a
conditionally lethal phenotype. E. coli mutants in pr1A (secY)
show defective export of proteins to the periplasm and outer
membrane. Recently we have shown that pr1A (secY) can
function in a posttranslational manner and that pr1A (secY) is
required for translocation of proOmpA into inner membrane
vesicles in vitro. This finding will allow a complementation assay
to be developed for isolation of a functional pr1A (secY) protein.
Studies examining the membrane topology of pr1A (secY) and its
binding to leader peptides and preproteins are proposed. Other
functional characterizations will include the interaction of pr1A
(secY) with ATP, its influence on the generation and maintenance
of the membrane electrochemical potential, and its possible
interaction with soluble components of the export machinery such
as secA. The eventual goal of this research is to purify the pr1A
(secY) protein in a functional state and determine its catalytic
role in protein export.
StatusFinished
Effective start/end date4/1/873/31/92

Funding

  • National Institutes of Health: $83,146.00
  • National Institutes of Health
  • National Institutes of Health
  • National Institutes of Health
  • National Institutes of Health

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Proteins
Periplasm
Mutation
Membranes
Membrane Lipids
Protein Sorting Signals
Membrane Potentials
Adenosine Triphosphate
Escherichia coli
Phenotype
Research
In Vitro Techniques

ASJC

  • Medicine(all)