Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Determinants of heat resistance in Escherichia coli AW1.7

ABSTRACT: Microarray hybridization of cDNA libraries obtained from exponentially growing or heat-shocked AW1.7 or GGG10 cultures was performed to compare gene expression of these two strains. Expression of selected genes from different functional groups was quantified by quantitative PCR (q-PCR). DnaK, 30S and 50S risobomal subunits were overexpressed in E. coli GGG10 relative to E. coli AW1.7 upon heat shock at 50M-BM-0C, indicating improved ribosome stability. The outer membrane porin NmpC and several transport proteins were overexpressed in exponentially growing E. coli AW1.7. Gene expression of a heat resistant strain, E. coli AW1.7, was compared to gene expression in a heat sensitive strain, E coli GGG10. RNA was isolated from late exponential cultures, or from late exponential cells heat-shocked by exposure to 50M-BM-0C for 15 min. Three independent biological repeats were analyzed, and technical repeats (dye-swap) were performed for two of three biological repeats.

ORGANISM(S): Escherichia coli

SUBMITTER: Michael GM-CM-$nzle

PROVIDER: E-GEOD-27607 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Solute transport proteins and the outer membrane protein NmpC contribute to heat resistance of Escherichia coli AW1.7.

Ruan Lifang L Pleitner Aaron A Gänzle Michael G MG McMullen Lynn M LM

Applied and environmental microbiology 20110311 9

This study aimed to elucidate determinants of heat resistance in Escherichia coli by comparing the composition of membrane lipids, as well as gene expression, in heat-resistant E. coli AW1.7 and heat-sensitive E. coli GGG10 with or without heat shock. The survival of E. coli AW1.7 at late exponential phase was 100-fold higher than that of E. coli GGG10 after incubation at 60°C for 15 min. The cytoplasmic membrane of E. coli AW1.7 contained a higher proportion of saturated and cyclopropane fatty ...[more]

PMID: 21398480

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Dataset Information

Determinants of heat resistance in Escherichia coli AW1.7

Publications

Solute transport proteins and the outer membrane protein NmpC contribute to heat resistance of Escherichia coli AW1.7.

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