Abstract
Four strains ofRhizobium (R. trifolii RCL10,R. japonicum S19 and SB16, andRhizobium sp. NEA4) were demonstrated to grow lithoautotrophically with molecular hydrogen as sole electron donor and with ammonium or with N2 as N source. All of them showed ribulose-1,5-bisphosphate carboxylase activity and hydrogenase (H2-uptake) activity with methylene blue and oxygen as electron acceptors. ForR. japonicum SB 16, a doubling time under autotrophic conditions of 30 h and a specific hydrogenase activity (methylene blue reduction) in crude extracts of 1.4 U/mg protein were calculated.Rhizobium hydrogenase is a membrane-bound enzyme. It is mainly detectable in particulate cell fractions, it cross-reacts with the antibodies of the membrane-bound hydrogenase ofAlcaligenes eutrophus, and is unable to reduce NAD. The isolated hydrogenase is a relatively oxygen-sensitive enzyme with a half-life of three days when stored at 4°C under air.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
