Co-Consumption of Methanol and Succinate by Methylobacterium extorquens AM1

• Published in: PloS one Vol. 7; no. 11; p. e48271
• Main Authors: Peyraud, Rémi, Kiefer, Patrick, Christen, Philipp, Portais, Jean-Charles, Vorholt, Julia A.
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 01.11.2012; Public Library of Science (PLoS)
• Subjects: Acids; Adaptation; Adenosine Triphosphate - chemistry; Amino acids; Analysis; Assimilation; Bacteria; Bacterial Physiological Phenomena; Bacterial Proteins - metabolism; Biochemistry - methods; Biology; Carbon; Carbon dioxide; Carbon Dioxide - chemistry; Carbon Isotopes - chemistry; Chromatography; Chromatography, Liquid - methods; Dehydrogenases; Environmental conditions; Enzymes; Genes; Gluconeogenesis; Growth conditions; Growth rate; Heterotrophic growth; Life Sciences; Liquid chromatography; Mass spectrometry; Mass Spectrometry - methods; Mass spectroscopy; Metabolism; Metabolites; Methanol; Methanol - metabolism; Methylobacterium extorquens - metabolism; Models, Statistical; NAD - chemistry; NADP - chemistry; Physiological aspects; Studies; Substrates; Succinic Acid - metabolism; Tetrahydrofolic acid; France
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0048271

Methylobacterium extorquens AM1 is a facultative methylotrophic Alphaproteobacterium and has been subject to intense study under pure methylotrophic as well as pure heterotrophic growth conditions in the past. Here, we investigated the metabolism of M. extorquens AM1 under mixed substrate conditions, i.e., in the presence of methanol plus succinate. We found that both substrates were co-consumed, and the carbon conversion was two-thirds from succinate and one-third from methanol relative to mol carbon. (13)C-methanol labeling and liquid chromatography mass spectrometry analyses revealed the different fates of the carbon from the two substrates. Methanol was primarily oxidized to CO(2) for energy generation. However, a portion of the methanol entered biosynthetic reactions via reactions specific to the one-carbon carrier tetrahydrofolate. In contrast, succinate was primarily used to provide precursor metabolites for bulk biomass production. This work opens new perspectives on the role of methylotrophy when substrates are simultaneously available, a situation prevailing under environmental conditions.