Abstract
The activation of the Fe protein of nitrogenase (Rr2) from glutamate-grown Rhodospirillum rubrum by activating enzyme (AE) was investigated. AE is confirmed to have Mr about 20 000 and is shown to operate catalytically. There is a role in activation for metal-ion-ATP, which can be met by either MnATP or MgATP. There is also a site of action for free metal ions. This site prefers Mn2+ (apparent Kd approx. 20 microM) over Mg2+ (apparent Kd approx. 20 mM) by a factor of 1000-fold. Non-activated Rr2 does not contain this binding site. MnATP is an inhibitor of C2H2 reduction, and excess Mg2+ inhibits both AE activity and C2H2 reduction, when each is studied independently under otherwise optimal conditions. The activity of AE is increased in normal reaction mixtures (in which AE activity and nitrogenase activity occur simultaneously) by Mg2+ concentrations in excess of ATP concentrations; this occurs because the excess Mg2+ prevents ATP from chelating the free Mn2+ necessary for optimal AE activity.
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Selected References
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- Brill W. J. Biochemical genetics of nitrogen fixation. Microbiol Rev. 1980 Sep;44(3):449–467. doi: 10.1128/mr.44.3.449-467.1980. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Burns R. C., Bulen W. A. A procedure for the preparation of extracts from Rhodospirillum rubrum catalyzing N2 reduction and ATP-dependent H2 evolution. Arch Biochem Biophys. 1966 Feb;113(2):461–463. doi: 10.1016/0003-9861(66)90215-3. [DOI] [PubMed] [Google Scholar]
- Burris R. H. Nitrogen fixation--assay methods and techniques. Methods Enzymol. 1972;24:415–431. doi: 10.1016/0076-6879(72)24088-5. [DOI] [PubMed] [Google Scholar]
- COHN M. MAGNETIC RESONANCE STUDIES OF METAL ACTIVATION OF ENZYMIC REACTIONS OF NUCLEOTIDES AND OTHER PHOSPHATE SUBSTRATES. Biochemistry. 1963 Jul-Aug;2:623–629. doi: 10.1021/bi00904a001. [DOI] [PubMed] [Google Scholar]
- Carithers R. P., Yoch D. C., Arnon D. I. Two forms of nitrogenase from the photosynthetic bacterium Rhodospirillum rubrum. J Bacteriol. 1979 Feb;137(2):779–789. doi: 10.1128/jb.137.2.779-789.1979. [DOI] [PMC free article] [PubMed] [Google Scholar]
- GOA J. A micro biuret method for protein determination; determination of total protein in cerebrospinal fluid. Scand J Clin Lab Invest. 1953;5(3):218–222. doi: 10.3109/00365515309094189. [DOI] [PubMed] [Google Scholar]
- Gotto J. W., Yoch D. C. Purification and Mn2+ activation of Rhodospirillum rubrum nitrogenase activating enzyme. J Bacteriol. 1982 Nov;152(2):714–721. doi: 10.1128/jb.152.2.714-721.1982. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gotto J. W., Yoch D. C. Regulation of Rhodospirillum rubrum nitrogenase activity. Properties and interconversion of active and inactive Fe protein. J Biol Chem. 1982 Mar 25;257(6):2868–2873. [PubMed] [Google Scholar]
- Hirose M., Kano Y. Binding of ligands by proteins: a simple method with Sephadex gel. Biochim Biophys Acta. 1971 Dec 28;251(3):376–379. doi: 10.1016/0005-2795(71)90125-5. [DOI] [PubMed] [Google Scholar]
- Ljones T., Burris R. H. Nitrogenase: the reaction between the Fe protein and bathophenanthrolinedisulfonate as a probe for interactions with MgATP. Biochemistry. 1978 May 16;17(10):1866–1872. doi: 10.1021/bi00603a010. [DOI] [PubMed] [Google Scholar]
- Ludden P. W., Burris R. H. Activating factor for the iron protein of nitrogenase from Rhodospirillum rubrum. Science. 1976 Oct 22;194(4263):424–426. doi: 10.1126/science.824729. [DOI] [PubMed] [Google Scholar]
- Ludden P. W., Burris R. H. Purification and properties of nitrogenase from Rhodospirillum rubrum, and evidence for phosphate, ribose and an adenine-like unit covalently bound to the iron protein. Biochem J. 1978 Oct 1;175(1):251–259. doi: 10.1042/bj1750251. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ludden P. W., Burris R. H. Removal of an adenine-like molecule during activation of dinitrogenase reductase from Rhodospirillum rubrum. Proc Natl Acad Sci U S A. 1979 Dec;76(12):6201–6205. doi: 10.1073/pnas.76.12.6201. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ludden P. W., Preston G. G., Dowling T. E. Comparison of active and inactive forms of iron protein from Rhodospirillum rubrum. Biochem J. 1982 Jun 1;203(3):663–668. doi: 10.1042/bj2030663. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Munson T. O., Burris R. H. Nitrogen fixation by Rhodospirillum rubrum grown in nitrogen-limited continuous culture. J Bacteriol. 1969 Mar;97(3):1093–1098. doi: 10.1128/jb.97.3.1093-1098.1969. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nordlund S., Eriksson U., Baltscheffsky H. Necessity of a membrane component for nitrogenase activity in Rhodospirillum rubrum. Biochim Biophys Acta. 1977 Oct 12;462(1):187–195. doi: 10.1016/0005-2728(77)90201-8. [DOI] [PubMed] [Google Scholar]
- Nordlund S., Eriksson U., Baltscheffsky H. Properties of the nitrogenase system from a photosynthetic bacterium, Rhodospirillum rubrum. Biochim Biophys Acta. 1978 Nov 9;504(2):248–254. doi: 10.1016/0005-2728(78)90173-1. [DOI] [PubMed] [Google Scholar]
- Nowak T., Mildvan A. S., Kenyon G. L. Nuclear relaxation and kinetic studies of the role of Mn 2+ in the mechanism of enolase. Biochemistry. 1973 Apr 24;12(9):1690–1701. doi: 10.1021/bi00733a005. [DOI] [PubMed] [Google Scholar]
- Nowak T., Mildvan A. S. Stereoselective interactions of phosphoenolpyruvate analogues with phosphoenolpyruvate-utilizing enzymes. J Biol Chem. 1970 Nov 25;245(22):6057–6064. [PubMed] [Google Scholar]
- ORMEROD J. G., ORMEROD K. S., GEST H. Light-dependent utilization of organic compounds and photoproduction of molecular hydrogen by photosynthetic bacteria; relationships with nitrogen metabolism. Arch Biochem Biophys. 1961 Sep;94:449–463. doi: 10.1016/0003-9861(61)90073-x. [DOI] [PubMed] [Google Scholar]
- Thorneley R. N., Willison K. R. Nitrogenase of Klebsiella pneumoniae. Inhibition of acetylene reduction by magnesium ion explained by the formation of an inactive dimagnesium-adenosine triphophate complex. Biochem J. 1974 Apr;139(1):211–214. doi: 10.1042/bj1390211. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tso M. Y., Burris R. H. The binding of ATP and ADP by nitrogenase components from Clostridium pasteurianum. Biochim Biophys Acta. 1973 Jun 6;309(2):263–270. doi: 10.1016/0005-2744(73)90024-7. [DOI] [PubMed] [Google Scholar]
- Yoch D. C. Manganese, an essential trace element for N2 fixation by Rhodospirillum rubrum and Rhodopseudomonas capsulata: role in nitrogenase regulation. J Bacteriol. 1979 Dec;140(3):987–995. doi: 10.1128/jb.140.3.987-995.1979. [DOI] [PMC free article] [PubMed] [Google Scholar]
