Abstract
1. A pathway for the synthesis of hexose from succinate by Rhodospirillum rubrum is proposed. 2. With 2,3-14C2-labelled succinate and fumarate as substrates in experiments with chromatophores and a soluble enzyme fraction of R. rubrum it was found that the products of succinate metabolism by the extracts were the same as in whole cells. It was also found that the light-dependent oxidation of succinate was catalysed by the chromatophores, but that all the other enzymes involved were in the soluble fraction. 3. By using specific assays the presence of all the enzymes required for the proposed pathway was demonstrated in the extracts and their specific activities were measured. 4. The overall rate of succinate assimilation was measured manometrically. The activities of the enzymes assayed were sufficient to account for the overall rate of assimilation. It is concluded that the proposed pathway represents the major mechanism for synthesis of hexose from succinate in R. rubrum. 5. The formation of alanine and aspartate was observed in experiments with isotopically labelled substrates, and possible synthetic pathways for these compounds are discussed.
Full text
PDF








Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- CAVALLINI D. The coupled oxidation of pyruvate with glutathione and cysteine. Biochem J. 1951 Jun;49(1):1–5. doi: 10.1042/bj0490001. [DOI] [PMC free article] [PubMed] [Google Scholar]
- ELSDEN S. R., ORMEROD J. G. The effect of monofluoroacetate on the metabolism of Rhodospirillum rubrum. Biochem J. 1956 Aug;63(4):691–701. doi: 10.1042/bj0630691. [DOI] [PMC free article] [PubMed] [Google Scholar]
- EVANS M. C. THE PHOTO-OXIDATION OF SUCCINATE BY CHROMATOPHORES OF RHODOSPIRILLUM RUBRUM. Biochem J. 1965 Jun;95:661–668. doi: 10.1042/bj0950661. [DOI] [PMC free article] [PubMed] [Google Scholar]
- GELLER D. M., LIPMANN F. Photophosphorylation in extracts of Rhodospirillum rubrum. J Biol Chem. 1960 Aug;235:2478–2484. [PubMed] [Google Scholar]
- HIRSCH P., SCHLEGEL H. G. CO2-FIXIERUNG DURCH KNALLGASBAKTERIEN. I. EINBAU UND FRAKTIONIERUNG. Arch Mikrobiol. 1963 Jul 18;46:44–52. [PubMed] [Google Scholar]
- KNIGHT M. The photometabolism of propionate by Rhodospirillum rubrum. Biochem J. 1962 Jul;84:170–185. doi: 10.1042/bj0840170. [DOI] [PMC free article] [PubMed] [Google Scholar]
- LASCELLES J. The formation of ribulose 1:5-diphosphate carboxylase by growing cultures of Athiorhodaceae. J Gen Microbiol. 1960 Dec;23:499–510. doi: 10.1099/00221287-23-3-499. [DOI] [PubMed] [Google Scholar]
- MENDICINO J., UTTER M. F. Interaction of soluble and mitochondrial multienzyme systems in hexose phosphate synthesis. J Biol Chem. 1962 May;237:1716–1722. [PubMed] [Google Scholar]
- ORMEROD J. G. The use of radioactive carbon dioxide in the measurement of carbon dioxide fixation in Rhodospirillum rubrum. Biochem J. 1956 Oct;64(2):373–380. doi: 10.1042/bj0640373. [DOI] [PMC free article] [PubMed] [Google Scholar]
- SZYMONA M., DOUDOROFF M. Carbohydrate metabolism in Rhodopseudomonas sphreoides. J Gen Microbiol. 1960 Feb;22:167–183. doi: 10.1099/00221287-22-1-167. [DOI] [PubMed] [Google Scholar]
- Stanier R. Y., Doudoroff M., Kunisawa R., Contopoulou R. THE ROLE OF ORGANIC SUBSTRATES IN BACTERIAL PHOTOSYNTHESIS. Proc Natl Acad Sci U S A. 1959 Aug;45(8):1246–1260. doi: 10.1073/pnas.45.8.1246. [DOI] [PMC free article] [PubMed] [Google Scholar]