On the relationship between affinity for molecular hydrogen and the physiological directionality of hydrogenases.
The physiological significance of the generic reaction H(2)<-->2[H] is not always clear because hydrogenases may function in the breakdown of molecular hydrogen or in its synthesis or in both directions. Fe-hydrogenases have nevertheless been most often associated with proton reduction and NiFe-hydrogenases with hydrogen oxidation. A re-determination of the K(M) of H(2) oxidation by Pyrococcus furiosus NiFe-hydrogenase-I and by Desulfovibrio vulgaris Fe-hydrogenase suggests that affinity for hydrogen has been seriously underestimated and that the kinetics of hydrogen activation in relation to the directionality of hydrogenases should be re-evaluated.
van Haaster
D J
DJ
Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands.
Hagedoorn
P-L
PL
Jongejan
J A
JA
Hagen
W R
WR
D006859:Hydrogen / Q000378:metabolism*; D006864:Hydrogenase / Q000378:metabolism*; D007700:Kinetics; D010084:Oxidation-Reduction
D006859:Hydrogen; C043296:nickel-iron hydrogenase; D006864:Hydrogenase