TY - JOUR
T1 - How Escherichia coli is equipped to oxidize hydrogen under different redox conditions
AU - Lukey, M.J.
AU - Parkin, A.
AU - Roessler, M.M.
AU - Murphy, B.J.
AU - Harmer, J.
AU - Armstrong, F.A.
AU - Palmer, T.
AU - Sargent, F.
N1 - Erratum published June 25, 2010 The Journal of Biological Chemistry, 285, 20421
PY - 2010/2/5
Y1 - 2010/2/5
N2 - The enterobacterium Escherichia coli synthesizes two H uptake enzymes, Hyd-1 and Hyd-2. We show using precise electrochemical kinetic measurements that the properties of Hyd-1 and Hyd-2 contrast strikingly, and may be individually optimized to function under distinct environmental conditions. Hyd-2 is well suited for fast and efficient catalysis in more reducing environments, to the extent that in vitro it behaves as a bidirectional hydrogenase. In contrast, Hyd-1 is active for H oxidation under more oxidizing conditions and cannot function in reverse. Importantly, Hyd-1 isO tolerant and can oxidize H in the presence of air, whereas Hyd-2 is ineffective for H oxidation under aerobic conditions. The results have direct relevance for physiological roles of Hyd-1 and Hyd-2, which are expressed in different phases of growth. The properties that we report suggest distinct technological applications of these contrasting enzymes.
AB - The enterobacterium Escherichia coli synthesizes two H uptake enzymes, Hyd-1 and Hyd-2. We show using precise electrochemical kinetic measurements that the properties of Hyd-1 and Hyd-2 contrast strikingly, and may be individually optimized to function under distinct environmental conditions. Hyd-2 is well suited for fast and efficient catalysis in more reducing environments, to the extent that in vitro it behaves as a bidirectional hydrogenase. In contrast, Hyd-1 is active for H oxidation under more oxidizing conditions and cannot function in reverse. Importantly, Hyd-1 isO tolerant and can oxidize H in the presence of air, whereas Hyd-2 is ineffective for H oxidation under aerobic conditions. The results have direct relevance for physiological roles of Hyd-1 and Hyd-2, which are expressed in different phases of growth. The properties that we report suggest distinct technological applications of these contrasting enzymes.
UR - http://www.scopus.com/inward/record.url?scp=77950503486&partnerID=8YFLogxK
U2 - 10.1074/jbc.M109.067751
DO - 10.1074/jbc.M109.067751
M3 - Article
AN - SCOPUS:77950503486
SN - 0021-9258
VL - 285
SP - 3928
EP - 3938
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 6
ER -