Analyses of the Polymorphisms in E. coli Strains Associated with Heat-Shock Proteins Hsp 55 Isolated from Bird Feathers

ABSTRACT The locus of heat resistance (LHR) is a 15- to 19-kb genomic island conferring exceptional heat resistance to organisms in the family Enterobacteriaceae, including pathogenic strains of Salmonella enterica and Escherichia coli. The complement of LHR-comprising genes that is necessary for heat resistance and the stress-induced or growth-phase-induced expression of LHR-comprising genes are unknown. This study determined the contribution of the seven LHR-comprising genes yfdX1 GI, yfdX2, hdeD GI, orf11, trx GI, kefB, and psiE GI by comparing the heat resistances of E. coli strains harboring plasmid-encoded derivatives of the different LHRs in these genes. (Genes carry a subscript “GI” [genomic island] if an ortholog of the same gene is present in genomes of E. coli.) LHR-encoded heat shock proteins sHSP20, ClpKGI, and sHSPGI are not sufficient for the heat resistance phenotype; YfdX1, YfdX2, and HdeD are necessary to complement the LHR heat shock proteins and to impart a high level of resistance. Deletion of trx GI, kefB, and psiE GI from plasmid-encoded copies of the LHR did not significantly affect heat resistance. The effect of the growth phase and the NaCl concentration on expression from the putative LHR promoter p2 was determined by quantitative reverse transcription-PCR and by a plasmid-encoded p2:GFP promoter fusion. The expression levels of exponential- and stationary-phase E. coli cells were not significantly different, but the addition of 1% NaCl significantly increased LHR expression. Remarkably, LHR expression in E. coli was dependent on a chromosomal copy of evgA. In conclusion, this study improved our understanding of the genes required for exceptional heat resistance in E. coli and factors that increase their expression in food. IMPORTANCE The locus of heat resistance (LHR) is a genomic island conferring exceptional heat resistance to several foodborne pathogens. The exceptional level of heat resistance provided by the LHR questions the control of pathogens by current food processing and preparation techniques. The function of LHR-comprising genes and their regulation, however, remain largely unknown. This study defines a core complement of LHR-encoded proteins that are necessary for heat resistance and demonstrates that regulation of the LHR in E. coli requires a chromosomal copy of the gene encoding EvgA. This study provides insight into the function of a transmissible genomic island that allows otherwise heat-sensitive enteric bacteria, including pathogens, to lead a thermoduric lifestyle and thus contributes to the detection and control of heat-resistant enteric bacteria in food.

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564 Genes Encoding E. coli Small Heat Shock Proteins IbpA/B Have a Protective Role in Experimental Colitis in E. coli Monoassociated Il10-Deficient Mice

Gastroenterology ◽

10.1016/s0016-5085(10)60359-9 ◽

2010 ◽

Vol 138 (5) ◽

pp. S-79 ◽

Cited By ~ 1

Author(s):

Laura G Patwa ◽

R. Balfour Sartor ◽

Jonathan J. Hansen

Keyword(s):

Heat Shock ◽

Heat Shock Proteins ◽

Experimental Colitis ◽

Protective Role ◽

Small Heat Shock Proteins ◽

E Coli ◽

Genes Encoding ◽

Shock Proteins ◽

Deficient Mice

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Comparative analysis of the molecular mechanism of heat shock proteins from pathogenic and non-pathogenic E.coli

10.1101/2020.06.17.157248 ◽

2020 ◽

Author(s):

Sanchari Bhattacharjee ◽

Mohana Saha ◽

Rakhi Dasgupta ◽

Angshuman Bagchi

Keyword(s):

Heat Shock ◽

Heat Shock Proteins ◽

Temperature Stress ◽

Small Heat Shock Proteins ◽

Lon Protease ◽

E Coli ◽

Physiological Temperature ◽

Mechanism Of Interaction ◽

Shock Proteins ◽

Catalytic Dyad

AbstractCells can withstand the effects of temperature stress by activating small heat shock proteins IbpA and IbpB. Lon protease employing Ser679 – Lys722 catalytic dyad proteolyze IbpA and IbpB in their free forms, at physiological temperature i.e. without any temperature stress. However, the proteolytic activity of IbpA and IbpB is affected when the catalytic dyad residue of Lon protease is mutated. The mutation S679A in Lon protease brings about some changes so that the proteolytic interactions between the small heat shock proteins with that of the mutant Lon protease are lost which makes a difference in the interaction pattern of mutant Lon protease with their substrates. In the present study, we made an attempt through in-silico approach to figure out the underlying aspects of the interactions between the small heat shock proteins IbpA and IbpB with mutant Lon protease in Escherichia coli. We have tried to decipher the molecular details of the mechanism of interaction of proteolytic machinery of small heat shock proteins and mutant Lon protease with S679A mutation at physiological temperature in absence cellular temperature stress. Our study may therefore be helpful to decode the mechanistic details of the correlation with IbpA, IbpB and S679A mutant Lon protease in E. coli.

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The Replication Initiator Protein of P1 Is Activated by two E. coli Heat Shock Proteins, DnaJ and DnaK

DNA Replication: The Regulatory Mechanisms ◽

10.1007/978-3-642-76988-7_31 ◽

1992 ◽

pp. 347-358

Author(s):

Sue Wickner ◽

Joel Hoskins ◽

Keith McKenney

Keyword(s):

Heat Shock ◽

Heat Shock Proteins ◽

E Coli ◽

Initiator Protein ◽

Replication Initiator Protein ◽

Shock Proteins ◽

Replication Initiator

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Heat Shock Protein-Mediated Resistance to High Hydrostatic Pressure in Escherichia coli

Applied and Environmental Microbiology ◽

10.1128/aem.70.5.2660-2666.2004 ◽

2004 ◽

Vol 70 (5) ◽

pp. 2660-2666 ◽

Cited By ~ 97

Author(s):

Abram Aertsen ◽

Kristof Vanoirbeek ◽

Philipp De Spiegeleer ◽

Jan Sermon ◽

Kristel Hauben ◽

...

Keyword(s):

Escherichia Coli ◽

High Pressure ◽

Hydrostatic Pressure ◽

Heat Shock ◽

Heat Shock Proteins ◽

High Hydrostatic Pressure ◽

Polyacrylamide Gel Electrophoresis ◽

Sodium Dodecyl ◽

E Coli ◽

Shock Proteins

ABSTRACT A random library of Escherichia coli MG1655 genomic fragments fused to a promoterless green fluorescent protein (GFP) gene was constructed and screened by differential fluorescence induction for promoters that are induced after exposure to a sublethal high hydrostatic pressure stress. This screening yielded three promoters of genes belonging to the heat shock regulon (dnaK, lon, clpPX), suggesting a role for heat shock proteins in protection against, and/or repair of, damage caused by high pressure. Several further observations provide additional support for this hypothesis: (i) the expression of rpoH, encoding the heat shock-specific sigma factor σ32, was also induced by high pressure; (ii) heat shock rendered E. coli significantly more resistant to subsequent high-pressure inactivation, and this heat shock-induced pressure resistance followed the same time course as the induction of heat shock genes; (iii) basal expression levels of GFP from heat shock promoters, and expression of several heat shock proteins as determined by two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis of proteins extracted from pulse-labeled cells, was increased in three previously isolated pressure-resistant mutants of E. coli compared to wild-type levels.

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