title: Methylovirgula ligni gen. nov., sp. nov., an obligately acidophilic, facultatively methylotrophic bacterium with a highly divergent mxaF gene.
abstract: Two strains of Gram-negative, aerobic, non-pigmented, non-motile, rod-shaped bacteria were isolated from beechwood blocks during decay by the white-rot fungus Hypholoma fasciculare and were designated strains BW863(T) and BW872. They are capable of methylotrophic growth and assimilate carbon via the ribulose-bisphosphate pathway. In addition to methanol, the novel isolates utilized ethanol, pyruvate and malate. Strains BW863(T) and BW872 are obligately acidophilic, mesophilic organisms capable of growth at pH 3.1-6.5 (with an optimum at pH 4.5-5.0) and at 4-30 degrees C. Phospholipid fatty acid profiles of these bacteria contain unusually large amounts (about 90 %) of C(18 : 1)omega7c, thereby resembling the profiles of Methylobacterium strains. The predominant quinone is Q-10. The DNA G+C content of the novel isolates is 61.8-62.8 mol%. On the basis of 16S rRNA gene sequence similarity, strains BW863(T) and BW872 are most closely related to the acidophilic methanotroph Methylocapsa acidiphila B2(T) (96.5-97 %). Comparative sequence analysis of mxaF, the gene encoding the large subunit of methanol dehydrogenase, placed the MxaF sequences of the two novel strains in a cluster that is distinct from all previously described MxaF sequences of cultivated methylotrophs. The identity between the MxaF sequences of the acidophilic isolates and those from known alpha-, beta- and gammaproteobacterial methylotrophs was respectively 69-75, 61-63 and 64-67 %. The data therefore suggest that strains BW863(T) and BW872 represent a novel genus and species of methylotrophic bacteria, for which the name Methylovirgula ligni gen. nov., sp. nov. is proposed. Strain BW863(T) (=DSM 19998(T) =NCIMB 14408(T)) is the type strain of Methylovirgula ligni.
authors.affiliation: S. N. Winogradsky Institute of Microbiology, Russian Academy of Sciences, Moscow 117312, Russia.
authors.forename: Alexey V
authors.initials: AV
authors.lastname: Vorob'ev
authors.forename: Wietse
authors.initials: W
authors.lastname: de Boer
authors.forename: Larissa B
authors.initials: LB
authors.lastname: Folman
authors.forename: Paul L E
authors.initials: PL
authors.lastname: Bodelier
authors.forename: Nina V
authors.initials: NV
authors.lastname: Doronina
authors.forename: Natalia E
authors.initials: NE
authors.lastname: Suzina
authors.forename: Yuri A
authors.initials: YA
authors.lastname: Trotsenko
authors.forename: Svetlana N
authors.initials: SN
authors.lastname: Dedysh
mesh_terms: D000143:Acids / Q000378:metabolism*; D000429:Alcohol Oxidoreductases / Q000235:genetics*; D052818:Autotrophic Processes; D001426:Bacterial Proteins / Q000235:genetics*; D042062:Beijerinckiaceae / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D004269:DNA, Bacterial / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D019143:Evolution, Molecular; D000432:Methanol / Q000378:metabolism*; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics
chemical_list: D000143:Acids; D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D000429:Alcohol Oxidoreductases; C019641:alcohol dehydrogenase (acceptor); D000432:Methanol