1987 Volume 33 Issue 6 Pages 521-542
The phenotypic and chemotaxonomic characteristics of methanol-utilizing Hyphomicrobium strains were examined and compared with other related budding bacteria. These Hyphomicrobium strains are facultatively methylotrophic, and utilize methanol, but not methane, by the serine pathway with formaldehyde incorporation. The strains were divided into two species, Hyphomicrobium vulgare and Hyphomicrobium methylovorum, based on DNA base composition, and the activities of catalase and urease. The major cellular fatty acid is straight-chain unsaturated C18:1 acid. The major ubiquinone is Q-9. Strains in other similar budding bacteria in the genera Hyphomonas, Pedomicrobium, Rhodomicrobium, and Hyphomicrobium indicum do not utilize methanol, have different DNA base compositions, possess different cellular fatty acids, and have different quinone systems. Based on the above data, the methanol-utilizing Hyphomicrobium strains are clearly distinguished from the supposedly related genera.