title: Hydrogenase in actinorhizal root nodules and root nodule homogenates.
abstract: Hydrogenases were measured in intact actinorhizal root nodules and from disrupted nodules of Alnus glutinosa, Alnus rhombifolia, Alnus rubra, and Myrica pensylvanica. Whole nodules took up H2 in an O2-dependent reaction. Endophyte preparations oxidized H2 through the oxyhydrogen reaction, but rates were enhanced when hydrogen uptake was coupled to artificial electron acceptors. Oxygen inhibited artifical acceptor-dependent H2 uptake. The hydrogenase system from M. pensylvanica had a different pattern of coupling to various electron acceptors than the hydrogenase systems from the alders; only the bayberry system evolved H2 from reduced viologen dyes.
mesh_terms: D000192:Actinomycetales / Q000201:enzymology*; D004579:Electron Transport; D006859:Hydrogen / Q000378:metabolism; D006864:Hydrogenase; D007700:Kinetics; D010088:Oxidoreductases / Q000378:metabolism*; D010100:Oxygen / Q000494:pharmacology; D010101:Oxygen Consumption; D010944:Plants / Q000201:enzymology* / Q000382:microbiology; D013559:Symbiosis
chemical_list: D006859:Hydrogen; D010088:Oxidoreductases; D006864:Hydrogenase; D010100:Oxygen