Enhanced export of beta-galactosidase fusion proteins in prlF mutants is Lon dependent.

Enhanced export of beta-galactosidase fusion proteins in prlF mutants is Lon dependent. Research Abstract Details 

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Enhanced export of beta-galactosidase fusion proteins in prlF mutants is Lon dependent. Abstract Text:

W B Snyder,T J Silhavy,

We have used fusions of the outer membrane protein LamB to beta-galactosidase (encoded by lacZ) to study the protein export process. This LamB-LacZ hybrid protein blocks export when synthesized at high levels, as evidenced by inducer (maltose) sensitivity, a phenomenon termed LacZ hybrid jamming. The prlF1 mutation relieves LacZ hybrid jamming and allows localization of the fusion protein to a noncytoplasmic compartment. prlF1 and similar alleles are gain-of-function mutations. Null mutations in this gene confer no obvious phenotypes. Extragenic suppressors of a gain-of-function prlF allele have been isolated in order to understand how this gene product affects the export process. The suppressors are all lon null mutations, and they are epistatic to all prlF phenotypes tested. Lon protease activity has been measured in prlF1 cells and shown to be increased. However, the synthesis of Lon is not increased in a prlF1 background, suggesting a previously unidentified mechanism of Lon activation. Further analysis reveals that prlF1 activates degradation of cytoplasmically localized precursors in a Lon protease-dependent manner. It is proposed that accumulation of precursors during conditions of hybrid protein jamming titrates an essential export component(s), possibly a chaperone. Increased Lon-dependent precursor degradation would free this component, thus allowing increased protein export under jamming conditions.

Enhanced export of beta-galactosidase fusion proteins in prlF mutants is Lon dependent. Publishing Authors By Initials

WB Snyder,TJ Silhavy,

For similar enzymes and coenzymes: enzymes: hydrolases: glycoside hydrolases: galactosidases: beta-galactosidase research abstracts see: enzymes and coenzymes: enzymes: hydrolases: glycoside hydrolases: galactosidases: beta-galactosidase research

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Enhanced export of beta-galactosidase fusion proteins in prlF mutants is Lon dependent. Journal Published:

PUBLICATION TYPE: Research Support, U.S. Gov't,

Journal: Journal of bacteriology

VOLUME: 174

Page Numbers: 5661-8

Journal Abbreviation: J. Bacteriol.

ISSN: 0021-9193

DAY: 27

MONTH: Sep

YEAR: 1992

Enhanced export of beta-galactosidase fusion proteins in prlF mutants is Lon dependent. Information

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LANGUAGE: eng

NlmUniqueID: 2985120

Enhanced export of beta-galactosidase fusion proteins in prlF mutants is Lon dependent. Keywords Mesh Terms:

KEYWORDS: beta-Galactosidase

MESH TERMS: genetics

Chemical & Substance for Abstract: Enhanced export of beta-galactosidase fusion proteins in prlF mutants is Lon dependent. Information

Substance Name: Protease La

Registry Number: EC 3.4.21.53

Grant and Affiliation Information for Enhanced export of beta-galactosidase fusion proteins in prlF mutants is Lon dependent.

AFFILIATION: Department of Molecular Biology, Princeton University, New Jersey 08544.

Country: UNITED STATES

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MEDLINETA: J Bacteriol

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Enhanced export of beta-galactosidase fusion proteins in prlF mutants is Lon dependent Related Publications

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