Abstract |
The hns gene is a member of the cold-shock regulon, indicating that the nucleoid-associated, DNA-binding protein H-NS plays an important role in the adaptation of Escherichia coli to low temperatures. We show here that the ability to cope efficiently with a cold environment (12 degrees C and 25 degrees C) is strongly impaired in E. coli strains carrying hns mutations. Growth inhibition is much more pronounced in strains carrying the hns-206 allele (an ampicillin resistance cassette inserted after codon 37) than in those carrying the hns-205 mutation (a Tn10 insertion located in codon 93). A protein fragment (H-NS*) is synthesized in strains carrying the hns-205::Tn10 mutation, suggesting that this truncated polypeptide is partially functional in the cold adaptation process. Analysis of the growth properties of strains harbouring four different low-copy-number plasmid-encoded hns' genes that result in the production of C-terminally truncated H-NS proteins supports this proposal. H-NS* proteins composed of 133, 117 or 94 amino-terminal amino acids partially complemented the severe cold-sensitive growth phenotype of the hns-206 mutant. In contrast, synthesis of a truncated H-NS protein with only 75 amino-terminal amino acids was insufficient to restore growth at low temperature.
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Authors | P Dersch, S Kneip, E Bremer |
Journal | Molecular & general genetics : MGG
(Mol Gen Genet)
Vol. 245
Issue 2
Pg. 255-9
(Oct 28 1994)
ISSN: 0026-8925 [Print] Germany |
PMID | 7816034
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Bacterial Outer Membrane Proteins
- Bacterial Proteins
- DNA-Binding Proteins
- H-NS protein, bacteria
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Topics |
- Adaptation, Physiological
(genetics)
- Bacterial Outer Membrane Proteins
(genetics, physiology)
- Bacterial Proteins
- Cold Temperature
- DNA-Binding Proteins
(genetics, physiology)
- Escherichia coli
(genetics, growth & development, physiology)
- Genetic Complementation Test
- Mutagenesis, Insertional
- Regulon
- Sequence Deletion
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