Abstract
This investigation revealed that the ribonucleotide reductases in extracts of Rhizobium leguminosarum, R. trifolii, R. phaseoli, R. japonicum, and R. meliloti 3DOal (ineffective in nitrogen fixation) are dependent upon B12 coenzyme for activity. Rhizobium and certain Lactobacillus species are the only two groups of organisms known to contain B12 coenzyme-dependent ribonucleotide reductases. Extracts of cobalt-deficient R. meliloti cells assayed in the presence of optimum B12 coenzyme showed a 5- to 10-fold greater ribonucleotide reductase activity than comparable extracts from cells grown on a complete medium. Furthermore, cobalt-deficient cells were abnormally elongated and contained reduced contents of deoxyribonucleic acid. The addition of purified deoxyribonucleosides to cobalt-deficient cultures of R. meliloti failed to alleviate deficiency symptoms.
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Selected References
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- ABRAMS R., LIBENSON L., EDMONDS M. Conversion of cytidine 5'-phosphate to deoxycytidine 5'-phosphate in cell-free mammalian extracts. Biochem Biophys Res Commun. 1960 Sep;3:272–274. doi: 10.1016/0006-291x(60)90238-2. [DOI] [PubMed] [Google Scholar]
- BECK W. S., HOOK S., BARNETT B. H. The metabolic functions of vitamin B12. I. Distinctive modes of unbalanced growth behavior in Lactobacillus leichmannii. Biochim Biophys Acta. 1962 Apr 2;55:455–469. doi: 10.1016/0006-3002(62)90978-2. [DOI] [PubMed] [Google Scholar]
- BLAKLEY R. L. COBAMIDES AND RIBONUCLEOTIDE REDUCTION. I. COBAMIDE STIMULATION OF RIBONUCLEOTIDE REDUCTION IN EXTRACTS OF LACTOBACILLUS LEICHMANNII. J Biol Chem. 1965 May;240:2173–2180. [PubMed] [Google Scholar]
- Beck W. S., Hardy J. Requirement of ribonucleotide reductase for cobamide coenzyme, a product of ribosomal activity. Proc Natl Acad Sci U S A. 1965 Jul;54(1):286–293. doi: 10.1073/pnas.54.1.286. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Blakley R. L. B12-dependent synthesis of deoxyribonucleotides. Fed Proc. 1966 Nov-Dec;25(6):1633–1638. [PubMed] [Google Scholar]
- Blakley R. L. Cobamides and ribonucleotide reduction. II. Estimation of the enzymic formation of purine and pyrimidine deoxyribonucleotides by the use of the diphenylamine reagent. J Biol Chem. 1966 Jan 10;241(1):176–179. [PubMed] [Google Scholar]
- Cowles J. R., Evans H. J. Some properties of the ribonucleotide reductase from Rhizobium meliloti. Arch Biochem Biophys. 1968 Sep 20;127(1):770–778. doi: 10.1016/0003-9861(68)90288-9. [DOI] [PubMed] [Google Scholar]
- DEHERTOGH A. A., MAYEUX P. A., EVANS H. J. THE RELATIONSHIP OF COBALT REQUIREMENT TO PROPIONATE METABOLISM IN RHIZOBIUM. J Biol Chem. 1964 Aug;239:2446–2453. [PubMed] [Google Scholar]
- DOWNING M., SCHWEIGERT B. S. Rôle of vitamin B12 in nucleic acid metabolism. IV. Metabolism of C14-labeled thymidine by Lactobacillus leichmannii. J Biol Chem. 1956 Jun;220(2):521–526. [PubMed] [Google Scholar]
- Goulian M., Beck W. S. Purification and properties of cobamide-dependent ribonucleotide reductase from Lactobacillus leichmannii. J Biol Chem. 1966 Sep 25;241(18):4233–4242. [PubMed] [Google Scholar]
- KITAY E., McNUTT W. S., SNELL E. E. Desoxyribosides and vitamin B12 as growth factors for lactic acid bacteria. J Bacteriol. 1950 Jun;59(6):727–738. doi: 10.1128/jb.59.6.727-738.1950. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kliewer M., Evans H. J. Cobamide Coenzyme Contents of Soybean Nodules & Nitrogen Fixing Bacteria in Relation to Physiological Conditions. Plant Physiol. 1963 Jan;38(1):99–104. doi: 10.1104/pp.38.1.99. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Koch B., Evans H. J., Russell S. Reduction of acetylene and nitrogen gas by breis and cell-free extracts of soybean root nodules. Plant Physiol. 1967 Mar;42(3):466–468. doi: 10.1104/pp.42.3.466. [DOI] [PMC free article] [PubMed] [Google Scholar]
- LOWE R. H., EVANS H. J. Cobalt requirement for the growth of rhizobia. J Bacteriol. 1962 Jan;83:210–211. doi: 10.1128/jb.83.1.210-211.1962. [DOI] [PMC free article] [PubMed] [Google Scholar]
- MOORE E. C., HURLBERT R. B. Reduction of 5'-cytidylic acid to deoxycytidylic acid by mammalian enzymes. Biochim Biophys Acta. 1960 May 20;40:371–372. doi: 10.1016/0006-3002(60)91371-8. [DOI] [PubMed] [Google Scholar]
- MOORE E. C., HURLBERT R. B. Reduction of cytidine nucleotides to deoxycytidine nucleotides by mammalian enzymes. Biochim Biophys Acta. 1962 May 14;55:651–663. doi: 10.1016/0006-3002(62)90843-0. [DOI] [PubMed] [Google Scholar]
- REICHARD P., BALDESTEN A., RUTBERG L. Formation of deoxycytidine phosphates from cytidine phosphates in extracts from Escherichia coli. J Biol Chem. 1961 Apr;236:1150–1157. [PubMed] [Google Scholar]
- REICHARD P., RUTBERG L. Formation of deoxycytidine 5'-phosphate from cytidine 5'-phosphate with enzymes from Escherichia coli. Biochim Biophys Acta. 1960 Jan 29;37:554–555. doi: 10.1016/0006-3002(60)90524-2. [DOI] [PubMed] [Google Scholar]
- REICHARD P. The biosynthesis of deoxyribonucleic acid by the chick embryo. IV. Formation of deoxycytidine and deoxyguanosine phosphates with soluble enzymes. J Biol Chem. 1961 Sep;236:2511–2513. [PubMed] [Google Scholar]