How Salmonella oxidises H(2) under aerobic conditions

TY - JOUR

T1 - How Salmonella oxidises H(2) under aerobic conditions

AU - Parkin, Alison

AU - Bowman, Lisa

AU - Roessler, Maxie M

AU - Davies, Rosalind A

AU - Palmer, Tracy

AU - Armstrong, Fraser A

AU - Sargent, Frank

N1 - Copyright © 2011 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

PY - 2012/3/9

Y1 - 2012/3/9

N2 - Salmonella enterica serovar Typhimurium is a Gram negative bacterial pathogen and a common cause of food-borne illness. Molecular hydrogen has been shown to be a key respiratory electron donor during infection and H(2) oxidation can be catalysed by three genetically-distinct [NiFe] hydrogenases. Of these, hydrogenases-1 (Hyd-1) and Hyd-2 have well-characterised homologues in Escherichia coli. The third, designated Hyd-5 here, is peculiar to Salmonella and is expressed under aerobic conditions. In this work, Salmonella was genetically modified to enable the isolation and characterisation of Hyd-5. Electrochemical analysis established that Hyd-5 is a H(2)-oxidising enzyme that functions in very low levels of H(2) and sustains this activity in high levels of O(2). In addition, electron paramagnetic resonance spectroscopy of the Hyd-5 isoenzyme reveals a complex paramagnetic FeS signal at high potentials which is comparable to that observed for other O(2)-tolerant respiratory [NiFe] hydrogenases. Taken altogether, Hyd-5 can be classified as an O(2)-tolerant hydrogenase that confers upon Salmonella the ability to use H(2) as an electron donor in aerobic respiration.

AB - Salmonella enterica serovar Typhimurium is a Gram negative bacterial pathogen and a common cause of food-borne illness. Molecular hydrogen has been shown to be a key respiratory electron donor during infection and H(2) oxidation can be catalysed by three genetically-distinct [NiFe] hydrogenases. Of these, hydrogenases-1 (Hyd-1) and Hyd-2 have well-characterised homologues in Escherichia coli. The third, designated Hyd-5 here, is peculiar to Salmonella and is expressed under aerobic conditions. In this work, Salmonella was genetically modified to enable the isolation and characterisation of Hyd-5. Electrochemical analysis established that Hyd-5 is a H(2)-oxidising enzyme that functions in very low levels of H(2) and sustains this activity in high levels of O(2). In addition, electron paramagnetic resonance spectroscopy of the Hyd-5 isoenzyme reveals a complex paramagnetic FeS signal at high potentials which is comparable to that observed for other O(2)-tolerant respiratory [NiFe] hydrogenases. Taken altogether, Hyd-5 can be classified as an O(2)-tolerant hydrogenase that confers upon Salmonella the ability to use H(2) as an electron donor in aerobic respiration.

UR - http://www.scopus.com/inward/record.url?scp=84857911690&partnerID=8YFLogxK

U2 - 10.1016/j.febslet.2011.07.044

DO - 10.1016/j.febslet.2011.07.044

M3 - Article

C2 - 21827758

VL - 586

SP - 536

EP - 544

JO - FEBS Letters

JF - FEBS Letters

IS - 5

ER -