Heat shock-induced excessive relaxation of DNA in Escherichia coli mutants lacking the histone-like protein HU

Yasuyuki Ogata, Ryu Ichi Inoue, Tohru Mizushima, Yasunobu Kano, Takeyoshi Miki, Kazuhisa Sekimizu

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

Plasmid DNA in exponentially growing Escherichia coli immediately relaxes after heat shock but the relaxed DNA re-supercoils rapidly, the despite continued presence of the heat shock conditions. We have now obtained genetic evidence indicating that the histone-like protein HU of E. coli is required for this re-supercoiling of DNA. Plasmid DNA in a hupA-hupB double gene-disruption mutant relaxed excessively after heat shock, while the relaxation of DNA in a himA-himD double gene-disruption mutant and in an hns insertion mutant was transient, thereby indicating that HU protein, but not IHF or H-NS proteins, is required for the re-supercoiling of DNA. Exposure of the hupA-hupB double mutant to a temperature of 50°C led to both excessive relaxation of DNA and to a decrease in viable cell number but temperatures lower than 46°C did not lead to these events. Based on these results, we propose that HU protein maintains the negative supercoiling of DNA during thermal stress and contributes to cellular thermotolerance in E. coli.

Original languageEnglish
Pages (from-to)298-306
Number of pages9
JournalBiochimica et Biophysica Acta - Gene Structure and Expression
Volume1353
Issue number3
DOIs
Publication statusPublished - 1997 Sep 12
Externally publishedYes

Fingerprint

Histones
Escherichia coli
Shock
Hot Temperature
DNA
Proteins
Plasmids
Genes
Temperature
Thermal stress
Cell Count

Keywords

  • Heat shock
  • Histone-like protein HU
  • Immediate and transient DNA relaxation
  • Supercoiling homeostasis
  • Thermotolerance

ASJC Scopus subject areas

  • Biochemistry
  • Genetics
  • Structural Biology
  • Biophysics

Cite this

Heat shock-induced excessive relaxation of DNA in Escherichia coli mutants lacking the histone-like protein HU. / Ogata, Yasuyuki; Inoue, Ryu Ichi; Mizushima, Tohru; Kano, Yasunobu; Miki, Takeyoshi; Sekimizu, Kazuhisa.

In: Biochimica et Biophysica Acta - Gene Structure and Expression, Vol. 1353, No. 3, 12.09.1997, p. 298-306.

Research output: Contribution to journalArticle

Ogata, Yasuyuki ; Inoue, Ryu Ichi ; Mizushima, Tohru ; Kano, Yasunobu ; Miki, Takeyoshi ; Sekimizu, Kazuhisa. / Heat shock-induced excessive relaxation of DNA in Escherichia coli mutants lacking the histone-like protein HU. In: Biochimica et Biophysica Acta - Gene Structure and Expression. 1997 ; Vol. 1353, No. 3. pp. 298-306.
@article{f9b54cd022124e00a76718a3c51edff2,
title = "Heat shock-induced excessive relaxation of DNA in Escherichia coli mutants lacking the histone-like protein HU",
abstract = "Plasmid DNA in exponentially growing Escherichia coli immediately relaxes after heat shock but the relaxed DNA re-supercoils rapidly, the despite continued presence of the heat shock conditions. We have now obtained genetic evidence indicating that the histone-like protein HU of E. coli is required for this re-supercoiling of DNA. Plasmid DNA in a hupA-hupB double gene-disruption mutant relaxed excessively after heat shock, while the relaxation of DNA in a himA-himD double gene-disruption mutant and in an hns insertion mutant was transient, thereby indicating that HU protein, but not IHF or H-NS proteins, is required for the re-supercoiling of DNA. Exposure of the hupA-hupB double mutant to a temperature of 50°C led to both excessive relaxation of DNA and to a decrease in viable cell number but temperatures lower than 46°C did not lead to these events. Based on these results, we propose that HU protein maintains the negative supercoiling of DNA during thermal stress and contributes to cellular thermotolerance in E. coli.",
keywords = "Heat shock, Histone-like protein HU, Immediate and transient DNA relaxation, Supercoiling homeostasis, Thermotolerance",
author = "Yasuyuki Ogata and Inoue, {Ryu Ichi} and Tohru Mizushima and Yasunobu Kano and Takeyoshi Miki and Kazuhisa Sekimizu",
year = "1997",
month = "9",
day = "12",
doi = "10.1016/S0167-4781(97)00105-X",
language = "English",
volume = "1353",
pages = "298--306",
journal = "Biochimica et Biophysica Acta - Gene Structure and Expression",
issn = "0167-4781",
publisher = "Elsevier BV",
number = "3",

}

TY - JOUR

T1 - Heat shock-induced excessive relaxation of DNA in Escherichia coli mutants lacking the histone-like protein HU

AU - Ogata, Yasuyuki

AU - Inoue, Ryu Ichi

AU - Mizushima, Tohru

AU - Kano, Yasunobu

AU - Miki, Takeyoshi

AU - Sekimizu, Kazuhisa

PY - 1997/9/12

Y1 - 1997/9/12

N2 - Plasmid DNA in exponentially growing Escherichia coli immediately relaxes after heat shock but the relaxed DNA re-supercoils rapidly, the despite continued presence of the heat shock conditions. We have now obtained genetic evidence indicating that the histone-like protein HU of E. coli is required for this re-supercoiling of DNA. Plasmid DNA in a hupA-hupB double gene-disruption mutant relaxed excessively after heat shock, while the relaxation of DNA in a himA-himD double gene-disruption mutant and in an hns insertion mutant was transient, thereby indicating that HU protein, but not IHF or H-NS proteins, is required for the re-supercoiling of DNA. Exposure of the hupA-hupB double mutant to a temperature of 50°C led to both excessive relaxation of DNA and to a decrease in viable cell number but temperatures lower than 46°C did not lead to these events. Based on these results, we propose that HU protein maintains the negative supercoiling of DNA during thermal stress and contributes to cellular thermotolerance in E. coli.

AB - Plasmid DNA in exponentially growing Escherichia coli immediately relaxes after heat shock but the relaxed DNA re-supercoils rapidly, the despite continued presence of the heat shock conditions. We have now obtained genetic evidence indicating that the histone-like protein HU of E. coli is required for this re-supercoiling of DNA. Plasmid DNA in a hupA-hupB double gene-disruption mutant relaxed excessively after heat shock, while the relaxation of DNA in a himA-himD double gene-disruption mutant and in an hns insertion mutant was transient, thereby indicating that HU protein, but not IHF or H-NS proteins, is required for the re-supercoiling of DNA. Exposure of the hupA-hupB double mutant to a temperature of 50°C led to both excessive relaxation of DNA and to a decrease in viable cell number but temperatures lower than 46°C did not lead to these events. Based on these results, we propose that HU protein maintains the negative supercoiling of DNA during thermal stress and contributes to cellular thermotolerance in E. coli.

KW - Heat shock

KW - Histone-like protein HU

KW - Immediate and transient DNA relaxation

KW - Supercoiling homeostasis

KW - Thermotolerance

UR - http://www.scopus.com/inward/record.url?scp=0030870386&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0030870386&partnerID=8YFLogxK

U2 - 10.1016/S0167-4781(97)00105-X

DO - 10.1016/S0167-4781(97)00105-X

M3 - Article

VL - 1353

SP - 298

EP - 306

JO - Biochimica et Biophysica Acta - Gene Structure and Expression

JF - Biochimica et Biophysica Acta - Gene Structure and Expression

SN - 0167-4781

IS - 3

ER -