title: A hydrogen-evolving enzyme is present in Frankia sp. R43.
abstract: The ability to evolve hydrogen using methyl viologen as an electron donor was assayed in the nitrogen-fixing actinomycetes Frankia sp. R43 and Frankia sp. KB5. To further examine the nature of hydrogen-evolving enzymes that may be present in these organisms immunological studies were performed. Under anaerobic conditions (both nitrogen-limiting and nitrogen-containing) Frankia sp. R43 but not Frankia sp. KB5 evolved hydrogen,which was not linked to NAD-reducing activity. Immunological analysis of total protein from Frankia sp. R43 and Frankia sp. KB5 using an antiserum raised against Ralstonia eutropha HoxF, recognized an antigen in Frankia sp. R43 but not in Frankia sp. KB5. Immunogold labeling using antibodies raised against the R. eutropha HoxH recognized sites in both hyphae and vesicles of Frankia sp. R43, but not in Frankia sp. KB5. Based on these physiological and immunological findings, we conclude that Frankia sp. R43 has a hydrogen-evolving hydrogenase.
authors.affiliation: Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, S-901 87 Umeå, Sweden.
authors.forename: Anasuya
authors.initials: A
authors.lastname: Mohapatra
authors.forename: Melakeselam
authors.initials: M
authors.lastname: Leul
authors.forename: Ulrika
authors.initials: U
authors.lastname: Mattsson
authors.forename: Anita
authors.initials: A
authors.lastname: Sellstedt
mesh_terms: D000693:Anaerobiosis; D001426:Bacterial Proteins / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism; D015153:Blotting, Western; D020118:Cupriavidus necator / Q000201:enzymology / Q000276:immunology; D040161:Frankia / Q000737:chemistry / Q000201:enzymology* / Q000276:immunology; D006859:Hydrogen / Q000378:metabolism*; D006864:Hydrogenase / Q000276:immunology / Q000378:metabolism*; D025301:Hyphae / Q000201:enzymology; D007150:Immunohistochemistry; D009243:NAD / Q000378:metabolism; D010269:Paraquat / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D009243:NAD; D006859:Hydrogen; D006864:Hydrogenase; D010269:Paraquat