Nocardia opaca hydrogenase

Noble metals, complex stability of, 3 267-268 Nocardia opaca hydrogenase, 32 315, 321-322... 

Among the diversity of Ni hydrogenases, there is a common pattern of protein composition, to which most conform, which consists of two protein subunits of relative molecular mass approximately 60,000 and 30,000 Da (14). There is some evidence (38) that the nickel is situated in the 60,000-Da subunit. More complex hydrogenases, such as the soluble hydrogenase of Nocardia opaca (Table I), contain other subunits which are concerned with the reduction of specific electron acceptors. 

Fig. 11. Dissociation and reassociation of soluble, NAD-linked hydrogenase from Nocardia opaca. Diaphorase refers to NADH acceptor reductase activity. Reproduced, with permission, from Ref. 82.

Aerobic bacteria such as Azotobacter vinelandii, Alcaligenes eutrophus, and Nocardia opaca, and facultative anaerobes, such as Escherichia coli and various species of Rhizobium and Bradyrhizobium (the symbionts of leguminous plants), also contain hydrogenase, as do photosynthetic bacteria such as Chromatium vinosum, Rhodobacter capsulatus (formerly Rhodopseudomonas capsulata), and Anabaena variabilis (a filamentous cyanobacterium). The thermophilic hydro-... 

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