Methylorubrum

Abstract Me.thy.lo.ru'brum. N.L. neut. n. methylum , the methyl radical; N.L. neut. n. methyl‐ , pertaining to the methyl radical; L. masc. adj. ruber , red; N.L. neut. n. Methylorubrum , a red methyl radical utilizing organism. Proteobacteria / Alphaproteobacteria / Rhizobiales / Methylobacteriaceae / Methylorubrum The genus Methylorubrum was split from the genus Methylobacterium to accommodate a phylogenetically distinct group of strains within Methylobacteriaceae . Members of this genus are pink to red‐pigmented, facultatively methylotrophic bacteria that assimilate single carbon substrates via the serine cycle. All species form pink to orange‐red colonies on methanol salts media; colonies are circular, convex with entire margins, and 0.5–3.0 mm in diameter. Cells are non‐spore‐forming rods that occur singly, in pairs, or occasionally in rosettes and may be branched or pleomorphic. Gram‐negative with a Gram‐negative cell wall type but may stain Gram‐variable. Cells of most species are motile by means of a polar, subpolar, or lateral flagellum. Respiration is strictly aerobic. Oxidase and catalase positive, although the oxidase reaction is often weak, and urease positive. Mesophilic, chemoorganotrophic, and facultatively methylotrophic. All strains grow on methanol, and most on formaldehyde, formate, and methylated amines. None grow on methane. Some strains have weakly phototrophic growth. Grow on various multicarbon compounds, in particular organic acids, and utilize a comparatively narrow range of mono‐ and disaccharides. All species grow on methylamine, and glycine betaine (where tested); few grow on citrate. The major cellular fatty acid is C 18:1 ω7 c . DNA G + C content is 64.4–70.5 ( T m ). Widely distributed in nature, being found in soil, water and associated with plants, as colonizers of leaf surfaces, or as endophytes. They form part of the human microflora and are found, rarely, in clinical samples. Methylorubrum extorquens is the type species of this genus. DNA G + C content (mol%) : 64.4–70.5 ( T m ). Type species : Methylorubrum extorquens Green and Ardley 2018 VP .