title: Hsp20, a small heat shock protein of Deinococcus radiodurans, confers tolerance to hydrogen peroxide in Escherichia coli.
abstract: The present study shows that DR1114 (Hsp20), a small heat shock protein of the radiationresistant bacterium Deinococcus radiodurans, enhances tolerance to hydrogen peroxide (H2O2) stress when expressed in Escherichia coli. A protein profile comparison showed that E. coli cells overexpressing D. radiodurans Hsp20 (EC-pHsp20) activated the redox state proteins, thus maintaining redox homeostasis. The cells also showed increased expression of pseudouridine (psi) synthases, which are important to the stability and proper functioning of structural RNA molecules. We found that the D. radiodurans mutant strain, which lacks a psi synthase (DR0896), was more sensitive to H2O2 stress than wild type. These suggest that an increased expression of proteins involved in the control of redox state homeostasis along with more stable ribosomal function may explain the improved tolerance of EC-pHsp20 to H2O2 stress.
authors.affiliation: Research Division for Biotechnology, Korea Atomic Energy Research Institute, Jeongeup 580-185, Republic of Korea.
authors.forename: Harinder
authors.initials: H
authors.lastname: Singh
authors.forename: Deepti
authors.initials: D
authors.lastname: Appukuttan
authors.forename: Sangyong
authors.initials: S
authors.lastname: Lim
mesh_terms: D003001:Cloning, Molecular; D034301:Deinococcus / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D004361:Drug Tolerance; D004926:Escherichia coli / Q000737:chemistry / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D029968:Escherichia coli Proteins / Q000032:analysis; D017353:Gene Deletion; D015870:Gene Expression; D050888:Heat-Shock Proteins, Small / Q000235:genetics* / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000633:toxicity*; D020543:Proteome / Q000032:analysis; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D013312:Stress, Physiological
chemical_list: D029968:Escherichia coli Proteins; D050888:Heat-Shock Proteins, Small; D020543:Proteome; D011994:Recombinant Proteins; D006861:Hydrogen Peroxide