Dataset Information

Chromosome and plasmid-borne P_LacO3O1 promoters differ in sensitivity to critically low temperatures.

ABSTRACT: Temperature shifts trigger genome-wide changes in Escherichia coli's gene expression. We studied if chromosome integration impacts on a gene's sensitivity to these shifts, by comparing the single-RNA production kinetics of a P_LacO3O1 promoter, when chromosomally-integrated and when single-copy plasmid-borne. At suboptimal temperatures their induction range, fold change, and response to decreasing temperatures are similar. At critically low temperatures, the chromosome-integrated promoter becomes weaker and noisier. Dissection of its initiation kinetics reveals longer lasting states preceding open complex formation, suggesting enhanced supercoiling buildup. Measurements with Gyrase and Topoisomerase I inhibitors suggest hindrance to escape supercoiling buildup at low temperatures. Consistently, similar phenomena occur in energy-depleted cells by DNP at 30?°C. Transient, critically-low temperatures have no long-term consequences, as raising temperature quickly restores transcription rates. We conclude that the chromosomally-integrated P_LacO3O1 has higher sensitivity to low temperatures, due to longer-lasting super-coiled states. A lesser active, chromosome-integrated native lac is shown to be insensitive to Gyrase overexpression, even at critically low temperatures, indicating that the rate of escaping positive supercoiling buildup is temperature and transcription rate dependent. A genome-wide analysis supports this, since cold-shock genes exhibit atypical supercoiling-sensitivities. This phenomenon might partially explain the temperature-sensitivity of some transcriptional programs of E. coli.

SUBMITTER: Oliveira SMD

PROVIDER: S-EPMC6418193 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Chromosome and plasmid-borne P<sub>LacO3O1</sub> promoters differ in sensitivity to critically low temperatures.

Oliveira Samuel M D SMD Goncalves Nadia S M NSM Kandavalli Vinodh K VK Martins Leonardo L Neeli-Venkata Ramakanth R Reyelt Jan J Fonseca Jose M JM Lloyd-Price Jason J Kranz Harald H Ribeiro Andre S AS

Scientific reports 20190314 1

Temperature shifts trigger genome-wide changes in Escherichia coli's gene expression. We studied if chromosome integration impacts on a gene's sensitivity to these shifts, by comparing the single-RNA production kinetics of a P<sub>LacO3O1</sub> promoter, when chromosomally-integrated and when single-copy plasmid-borne. At suboptimal temperatures their induction range, fold change, and response to decreasing temperatures are similar. At critically low temperatures, the chromosome-integrated promo ...[more]

PMID: 30872616

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Chromosome and plasmid-borne P_LacO3O1 promoters differ in sensitivity to critically low temperatures.

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Chromosome and plasmid-borne P<sub>LacO3O1</sub> promoters differ in sensitivity to critically low temperatures.

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Chromosome and plasmid-borne PLacO3O1 promoters differ in sensitivity to critically low temperatures.

Publications

Chromosome and plasmid-borne P<sub>LacO3O1</sub> promoters differ in sensitivity to critically low temperatures.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

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Chromosome and plasmid-borne P_LacO3O1 promoters differ in sensitivity to critically low temperatures.