Methylocapsa aurea sp. nov., a facultative methanotroph possessing a particulate methane monooxygenase, and emended description of the genus Methylocapsa.
An aerobic, methanotrophic bacterium, designated KYG(T), was isolated from a forest soil in Germany. Cells of strain KYG(T) were Gram-negative, non-motile, slightly curved rods that multiplied by binary fission and produced yellow colonies. The cells contained intracellular granules of poly-β-hydroxybutyrate at each cell pole, a particulate methane monooxygenase (pMMO) and stacks of intracytoplasmic membranes (ICMs) packed in parallel along one side of the cell envelope. Strain KYG(T) grew at pH 5.2-7.2 and 2-33 °C and could fix atmospheric nitrogen under reduced oxygen tension. The major cellular fatty acid was C(18 : 1)ω7c (81.5 %) and the DNA G+C content was 61.4 mol%. Strain KYG(T) belonged to the family Beijerinckiaceae of the class Alphaproteobacteria and was most closely related to the obligate methanotroph Methylocapsa acidiphila B2(T) (98.1 % 16S rRNA gene sequence similarity and 84.7 % pmoA sequence similarity). Unlike Methylocapsa acidiphila B2(T), which grows only on methane and methanol, strain KYG(T) was able to grow facultatively on acetate. Facultative acetate utilization is a characteristic of the methanotrophs of the genus Methylocella, but the genus Methylocella does not produce pMMO or ICMs. Strain KYG(T) differed from Methylocapsa acidiphila B2(T) on the basis of substrate utilization pattern, pigmentation, pH range, cell ultrastructure and efficiency of dinitrogen fixation. Therefore, we propose a novel species, Methylocapsa aurea sp. nov., to accommodate this bacterium. The type strain is KYG(T) (=DSM 22158(T) =VKM B-2544(T)).
Dunfield
Peter F
PF
Max-Planck-Institute for Terrestrial Microbiology, D-35043 Marburg, Germany.|Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada.
Belova
Svetlana E
SE
S. N. Winogradsky Institute of Microbiology, Russian Academy of Sciences, Moscow 117312, Russia.
Vorob'ev
Alexey V
AV
S. N. Winogradsky Institute of Microbiology, Russian Academy of Sciences, Moscow 117312, Russia.
Cornish
Sabrina L
SL
Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada.
Dedysh
Svetlana N
SN
S. N. Winogradsky Institute of Microbiology, Russian Academy of Sciences, Moscow 117312, Russia.
D052818:Autotrophic Processes; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001482:Base Composition; D042062:Beijerinckiaceae / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D004269:DNA, Bacterial / Q000235:genetics; D008697:Methane / Q000378:metabolism*; D008969:Molecular Sequence Data; D010105:Oxygenases / Q000235:genetics / Q000378:metabolism*; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012988:Soil Microbiology
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S; D010105:Oxygenases; C021555:methane monooxygenase; D008697:Methane