Evidence for the presence of the reductive pentose phosphate cycle in a filamentous anoxygenic photosynthetic bacterium, Oscillochloris trichoides strain DG-6

1 Department of Microbiology, Moscow State University, Moscow, 119899, Russia 2 Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino, 142292, Russia Author for correspondence: Ruslan N. Ivanovsky. Tel: -7 095 939 4203. Fax: -7 095 939 4658. e-mail: rusla...

Full description

Saved in:

Bibliographic Details
Published in:	Microbiology (Society for General Microbiology) Vol. 145; no. 7; pp. 1743 - 1748
Main Authors:	Ivanovsky, Ruslan N, Fal, Yuri I, Berg, Ivan A, Ugolkova, Natalya V, Krasilnikova, Elena N, Keppen, Olga I, Zakharchuc, Leonid M, Zyakun, Anatolii M
Format:	Journal Article
Language:	English
Published:	Reading Soc General Microbiol 01-07-1999 Society for General Microbiology
Subjects:	Bacteria - enzymology Bacteria - growth & development Carbon Dioxide - metabolism Carbon Radioisotopes - metabolism Citric Acid Cycle Oscillochloris trichoides Oxidation-Reduction Pentose Phosphate Pathway Phosphotransferases (Alcohol Group Acceptor) - metabolism Ribulose-Bisphosphate Carboxylase - metabolism
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	1 Department of Microbiology, Moscow State University, Moscow, 119899, Russia 2 Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino, 142292, Russia Author for correspondence: Ruslan N. Ivanovsky. Tel: -7 095 939 4203. Fax: -7 095 939 4658. e-mail: ruslan@protein.bio.msu.su ABSTRACT Studies on autotrophic CO 2 fixation by the filamentous anoxygenic photosynthetic bacterium Oscillochloris trichoides strain DG-6 demonstrated that, unlike other green bacteria, this organism metabolized CO 2 via the reductive pentose phosphate cycle. Both key enzymes of this cycle — ribulose-1,5-bisphosphate carboxylase/oxygenase and phosphoribulokinase — were detected in cell extracts. The main product of ribulose 1,5-bisphosphate-dependent CO 2 fixation was 3-phosphoglyceric acid. KCN, which is known to be a competitive inhibitor of ribulose-1,5-bisphosphate carboxylase/oxygenase, completely in hibited the CO 2 assimilation by whole cells as well as by cell extracts of O. trichoides. The 13 C/ 12 C carbon isotope fractionation during photoautotrophic growth of O. trichoides was -19·7°/ , which is close to that obtained for autotrophic organisms that use ribulose-1,5-bisphosphate carboxylase as the primary carboxylation enzyme. Cell extracts of O. trichoides contained all the enzymes of the tricarboxylic acid cycle except 2-oxoglutarate dehydrogenase. No activity of isocitrate lyase, a key enzyme of the glyoxylate shunt, was found in cell extracts of O. trichoides DG-6. Keywords: green bacteria, Oscillochloris trichoides, CO 2 fixation pathway, ribulose-1,5-bisphosphate carboxylase/oxygenase, tricarboxylic acid cycle
Bibliography:	ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23
ISSN:	1350-0872 1465-2080
DOI:	10.1099/13500872-145-7-1743