This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Ekiel, I Articles by Patel, G B Search for Related Content PubMed PubMed Citation Articles by Ekiel, I Articles by Patel, G B

Acetate and CO2 assimilation by Methanothrix concilii.

ABSTRACT

Biosynthetic pathways in Methanothrix concilii, a recently isolated aceticlastic methanogen, were studied by 13C-nuclear magnetic resonance spectroscopy. Labeling patterns of amino acids, lipids, and carbohydrates were determined. Similar to other methanogens, acetate was carboxylated to pyruvate, which was further converted to amino acids by various biosynthetic pathways. The origin of carbon atoms in glutamate, proline, and arginine clearly showed that an incomplete tricarboxylic acid cycle operating in the oxidative direction was used for their biosynthesis. Isoleucine was synthesized via citramalate, which is a typical route for methanogens. As with Methanosarcina barkeri, an extensive exchange of the label between the carboxyl group of acetate and CO2 was observed. Lipids predominantly contained diphytanyl chains, the labeling of which indicated that biosynthesis proceeded through mevalonic acid. Labeling of the C-1,6 of glucose from [2-13C]acetate is consistent with a glucogenic route for carbohydrate biosynthesis. Except for the different origins of the methyl group of methionine, the metabolic properties of Methanothrix concilii are closely related to those of Methanosarcina barkeri.

This article has been cited by other articles:

• Patel, H. M., Kraszewski, J. L., Mukhopadhyay, B. (2004). The Phosphoenolpyruvate Carboxylase from Methanothermobacter thermautotrophicus Has a Novel Structure. J. Bacteriol. 186: 5129-5137 [Abstract] [Full Text]  
• Hochuli, M., Patzelt, H., Oesterhelt, D., Wüthrich, K., Szyperski, T. (1999). Amino Acid Biosynthesis in the Halophilic Archaeon Haloarcula hispanica. J. Bacteriol. 181: 3226-3237 [Abstract] [Full Text]  
• Howell, D. M., Xu, H., White, R. H. (1999). (R)-Citramalate Synthase in Methanogenic Archaea. J. Bacteriol. 181: 331-333 [Abstract] [Full Text]