title: Requirement of carbon dioxide for initial growth of facultative methylotroph, Acidomonas methanolica MB58.
abstract: The facultative methylotrophic bacterium Acidomonas methanolica MB58 can utilize C1 compounds via the ribulose monophosphate pathway. A large gene cluster comprising three components related to C1 metabolism was found in the genome. From upstream, the first was an mxa cluster encoding proteins for oxidation of methanol to formaldehyde; the second was the rmp cluster encoding enzymes for formaldehyde fixation; and the third was the cbb gene cluster encoding proteins for carbon dioxide (CO2) fixation. Examination of CO2 requirements for growth of A. methanolica MB58 cells demonstrated that it did not grow on any carbon source under CO2-free conditions. Measurement of ribulose-1,5-bisphosphate carboxylase activity and RT-PCR analysis demonstrated enzymatic activity was detected in A. methanolica MB58 at growth phase, regardless of carbon sources. However, methanol dehydrogenase and 3-hexlose-6-phosphate synthase expression was regulated by methanol or formaldehyde; it were detected during growth and apparently differed from ribulose-1,5-bisphosphate carboxylase expression. These results suggested that A. methanolica MB58 may be initially dependent on autotrophic growth and that carbon assimilation was subsequently coupled with the ribulose monophosphate pathway at early- to mid-log phases during methylotrophic growth.
authors.affiliation: Department of Biochemistry, Faculty of Science, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama 700-0005, Japan. Electronic address: rmitsui@dbc.ous.ac.jp.
authors.forename: Ryoji
authors.initials: R
authors.lastname: Mitsui
authors.affiliation: Department of Biochemistry, Faculty of Science, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama 700-0005, Japan. Electronic address: k.hiroko@me.com.
authors.forename: Hiroko
authors.initials: H
authors.lastname: Katayama
authors.affiliation: Department of Biochemistry, Faculty of Science, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama 700-0005, Japan. Electronic address: mtanaka@dbc.ous.ac.jp.
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Tanaka
mesh_terms: D016947:Acetobacteraceae / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D000429:Alcohol Oxidoreductases / Q000378:metabolism; D002244:Carbon / Q000378:metabolism; D002245:Carbon Dioxide / Q000378:metabolism*; D005557:Formaldehyde / Q000378:metabolism; D005798:Genes, Bacterial / Q000235:genetics; D000432:Methanol / Q000378:metabolism; D005810:Multigene Family / Q000235:genetics; D010084:Oxidation-Reduction; D010788:Photosynthesis; D012273:Ribulose-Bisphosphate Carboxylase / Q000378:metabolism
chemical_list: D002245:Carbon Dioxide; D005557:Formaldehyde; D002244:Carbon; D000429:Alcohol Oxidoreductases; C019641:alcohol dehydrogenase (acceptor); D012273:Ribulose-Bisphosphate Carboxylase; D000432:Methanol
keywords: Acidomonas methanolica MB58; Calvin cycle; Carbon dioxide; Methylotroph bacteria; Ribulose monophosphate pathway