Resonance Raman studies of iron-only hydrogenases.
The nature of the iron-sulfur clusters in oxidized and reduced forms of Fe-only hydrogenases from Desulfovibrio vulgaris, Thermotoga maritima, and Clostridium pasteurianum has been investigated by resonance Raman spectroscopy. The results indicate the presence of ferredoxin-like [4Fe-4S]2+,+ and [2Fe-2S]2+,+ clusters in both T. maritima hydrogenase and C. pasteurianum hydrogenase I, but only [4Fe-4S]2+,+ clusters in D. vulgaris hydrogenase. This necessitates a reevaluation of the iron-sulfur cluster composition of C. pasteurianum hydrogenase I and indicates that the resonance Raman bands in the oxidized hydrogenase that were previously attributed to the hydrogen activating center [Macor, K. A., Czernuszewicz, R. S., Adams, M. W. W., & Spiro, T. G. (1987) J. Biol. Chem. 262, 9945-9947] arise from an indigenous [2Fe-2S]2+ cluster. No resonance Raman bands that could be uniquely attributed to the oxidized or reduced hydrogen activating center were observed. This suggests that the hydrogen activating center is a novel Fe center that is unrelated to any known type of Fe-S cluster.
Fu
W
W
Department of Chemistry, University of Georgia, Athens 30602.
Drozdzewski
P M
PM
Morgan
T V
TV
Mortenson
L E
LE
Juszczak
A
A
Adams
M W
MW
He
S H
SH
Peck
H D
HD
DerVartanian
D V
DV
LeGall
J
J
D003013:Clostridium / Q000201:enzymology*; D016969:Desulfovibrio vulgaris / Q000201:enzymology*; D006089:Gram-Negative Anaerobic Bacteria / Q000201:enzymology*; D006864:Hydrogenase / Q000737:chemistry* / Q000145:classification; D007501:Iron / Q000737:chemistry; D007506:Iron-Sulfur Proteins / Q000737:chemistry* / Q000145:classification; D013059:Spectrum Analysis, Raman; D013455:Sulfur / Q000737:chemistry
D007506:Iron-Sulfur Proteins; D013455:Sulfur; D007501:Iron; D006864:Hydrogenase