title: Isolation and characterization of bacterium producing lipid from short-chain fatty acids.
abstract: Anaerobic fermentation generates propionic acid, which inhibits microbial growth and accumulates in wastewater containing increased amounts of organic matter. We therefore isolated a propionic acid-assimilating bacterium that could produce triacylglycerol, for use in wastewater treatment. Nitratireductor sp. strain OM-1 can proliferate in medium containing propionic, acetic, butyric, and valeric acids as well as glycerol, and produces triacylglycerol when both propionic and acetic acids or glycerol are present. In composite model wastewater containing acetic acid, propionic acid and glycerol, this strain shows an even higher conversion rate, suggesting that it is suitable for wastewater treatment. Further, nitrogen depletion in medium containing an acetic-propionic acid mixture resulted in the production of the light oil 2-butenoic acid 1-methylethyl ester, but not triacylglycerol. Collectively, our data indicate that strain OM-1 has the potential to reduce accumulation of activated sludge in wastewater treatment and may contribute to the production of biodiesel.
authors.affiliation: Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530, Japan; CREST, JST, Sanbancho 5, Chiyoda-ku, Tokyo 102-0075, Japan. Electronic address: okamuray@hiroshima-u.ac.jp.
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Okamura
authors.affiliation: Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530, Japan.
authors.forename: Shota
authors.initials: S
authors.lastname: Nakai
authors.affiliation: Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530, Japan.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Ohkawachi
authors.affiliation: Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Suemitsu
authors.affiliation: Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530, Japan; CREST, JST, Sanbancho 5, Chiyoda-ku, Tokyo 102-0075, Japan.
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Takahashi
authors.affiliation: Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530, Japan; CREST, JST, Sanbancho 5, Chiyoda-ku, Tokyo 102-0075, Japan.
authors.forename: Tsunehiro
authors.initials: T
authors.lastname: Aki
authors.affiliation: Division of Energy and Environmental Engineering, Institute of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima 739-8527, Japan; CREST, JST, Sanbancho 5, Chiyoda-ku, Tokyo 102-0075, Japan.
authors.forename: Yukihiko
authors.initials: Y
authors.lastname: Matsumura
authors.affiliation: Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530, Japan; CREST, JST, Sanbancho 5, Chiyoda-ku, Tokyo 102-0075, Japan.
authors.forename: Takahisa
authors.initials: T
authors.lastname: Tajima
authors.affiliation: Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8530, Japan; CREST, JST, Sanbancho 5, Chiyoda-ku, Tokyo 102-0075, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Nakashimada
authors.affiliation: Biotechnology Laboratory, Electric Power Development Co., Ltd., Yanagisaki-machi, Wakamatsu-ku, Kitakyusyu 808-0111, Japan.
authors.forename: Mitsufumi
authors.initials: M
authors.lastname: Matsumoto
mesh_terms: D001419:Bacteria / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification* / Q000378:metabolism; D002244:Carbon / Q000494:pharmacology; D005232:Fatty Acids, Volatile / Q000378:metabolism* / Q000494:pharmacology; D005990:Glycerol / Q000494:pharmacology; D008055:Lipids / Q000096:biosynthesis*; D009584:Nitrogen / Q000494:pharmacology; D013997:Time Factors; D062065:Wastewater / Q000737:chemistry
chemical_list: D002244:Carbon; D005232:Fatty Acids, Volatile; D005990:Glycerol; D008055:Lipids; D009584:Nitrogen; D062065:Wastewater
keywords: Biodiesel; Light oil; Propionic acid; Triacylglycerol production; Wastewater treatment