The recA gene of Lactococcus lactis: characterization and involvement in oxidative and thermal stress

Molecular Microbiology
P DuwatA Gruss

Abstract

The role of recA in Lactococcus lactis, a microaerophilic fermenting organism, was examined by constructing a recA-disrupted strain. This single alteration had a surprisingly pleiotropic effect. In addition to its roles in homologous recombination and DNA repair, recA is also involved in responses to oxygen and heat stresses. We found that oxygen stress induced by aeration causes reductions in growth and stationary-phase survival of the recA strain. Toxicity is a consequence of hydroxyl radical production via the Fenton Reaction and is alleviated by catalase or Ferrozine addition. These results suggest that oxygen radicals are not efficiently eliminated and accumulate in lactococcal cultures, and that RecA is needed to deal with the damage they incur. Unexpectedly, thermal stress arrested growth of the recA strain. Immunological data indicate that the recA mutant is deficient in heat-shock proteins DnaK, GroEL, and GrpE. Poor growth at elevated temperature is therefore due to a diminished heat-shock response in the recA strain. In contrast, levels of a novel heat-shock protein, HfIB, are elevated. In Escherichia coli, HfIB downregulates the heat-shock response by promoting degradation of the transcription factor sigma 32. We pr...Continue Reading

Citations

Jan 1, 1996·Journal of Molecular Neuroscience : MN·I Gozes, D E Brenneman
Jul 23, 2011·Journal of Industrial Microbiology & Biotechnology·Ji-Cheng WangHe-Ping Zhang
May 24, 2006·Biometals : an International Journal on the Role of Metal Ions in Biology, Biochemistry, and Medicine·Yuji YamamotoPhilippe Gaudu
May 3, 2000·International Journal of Food Microbiology·P DuwatA Gruss
Sep 15, 2001·FEMS Microbiology Letters·A AmanatidouL G Gorris
May 22, 2001·Molecular Microbiology·G W LauD W Holden
Aug 7, 2007·Applied and Environmental Microbiology·Mark S TurnerPhilip M Giffard
Feb 5, 2005·Applied and Environmental Microbiology·Merete LundeIngolf F Nes
May 15, 2007·Journal of Bacteriology·R J W BrooijmansJ Hugenholtz
Dec 17, 2008·Journal of Bacteriology·Daniela FioccoGiuseppe Spano
Dec 26, 2001·Journal of Bacteriology·Ange-Patricia Tchamedeu KameniMathieu Picardeau
Sep 16, 2006·Microbial Cell Factories·Gabriele GilibertiMaurilio De Felice
Jan 22, 1998·Proceedings of the National Academy of Sciences of the United States of America·M el KarouiA Gruss
Oct 1, 1996·Antonie van Leeuwenhoek·F RalluE Maguin
Dec 21, 2010·Current Opinion in Biotechnology·Stijn van der Veen, Tjakko Abee
Sep 16, 2006·The Plant Journal : for Cell and Molecular Biology·Junping ChenZhanguo Xin
Nov 7, 2009·Microbiology·Stijn van der VeenMarjon H J Wells-Bennik
Mar 22, 2014·Journal of the Science of Food and Agriculture·Mengru ZhangGuocheng Du
Jan 9, 2014·PloS One·Patrick M ChongUNKNOWN Canadian Nosocomial Infection Surveillance Program (CNISP)
Oct 1, 1995·European Journal of Immunology·P P McDonaldG Pizzolo
Aug 6, 2013·Applied and Environmental Microbiology·Jun ChenPeter Ruhdal Jensen

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