NAD(P) + -dependent hydrogenase activity in extracts from the cyanobacterium Anacystis nidulans

Abstract

Sequence data had indicated that cyanobacteria might possess a bidirectional hydrogenase with properties similar to the sol. enzymes from Alcaligenes eutrophus, Nocardia opaca and Desulfovibrio fructosovorans. The present study shows that exts. from the cyanobacterium Anacystis nidulans catalyze NAD(P)H-dependent H2 evolution with low but significant activity and uptake of the gas with NAD(P)+ as the electron acceptor. NAD+ is the preferred electron acceptor and NADH the preferred donor compared to NADP+ and NADPH, resp. Activity levels of this NAD(P)+-dependent, bidirectional hydrogenase are too low to support chemoautotrophic growth in A. nidulans. [on SciFinder(R)]