Purification of Rhizobium leguminosarum HypB, a nickel-binding protein required for hydrogenase synthesis.

摘要: The products of the Rhizobium leguminosarum hyp gene cluster are necessary for synthesis a functional uptake [NiFe] hydrogenase system in symbiosis with pea plants, and at least HypB HypF, role hydrogenase-specific nickel metabolism has been postulated (L. Rey, J. Murillo, Y. Hernando, E. Hidalgo, Cabrera, Imperial, T. Ruiz-Argueso, Mol. Microbiol. 8:471-481, 1993). R. hypB product overexpressed Escherichia coli purified by immobilized chelate affinity chromatography single step. recombinant protein was able to bind 3.9 +/- 0.1 Ni2+ ions per monomer solution. Co2+, Cu2+, Zn2+ competed increasing efficiency. Monospecific antibodies were raised used show that is synthesized microaerobic vegetative cells bacteroids but not aerobic cells. could also be isolated chromatography. A histidine-rich region amino terminus (23-HGHHHH DGHHDHDHDHDHHRGDHEHDDHHH-54) proposed play binding, both solution chelated form.