Methylocapsa polymorpha sp. nov., a Novel Dinitrogen-Fixing Methanotroph from a Subarctic Wetland

• Published in: Microbiology (New York) Vol. 92; no. Suppl 1; pp. S107 - S113
• Main Authors: Belova, S. E., Oshkin, I. Y., Miroshnikov, K. K., Suzina, N. E., Danilova, O. V., Dedysh, S. N.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.12.2023; Springer Nature B.V
• Subjects: Acetic acid; Biomedical and Life Sciences; Cytology; Electron microscopy; Genomes; Life Sciences; Medical Microbiology; Membrane vesicles; Methane monooxygenase; Methanotrophic bacteria; Microbiology; New species; Nucleotide sequence; Peat; rRNA 16S; Short Communications; subarctic peatlands; growth on acetate; methanotrophic bacteria; genome analysis; dinitrogen fixation
• ISSN: 0026-2617; 1608-3237
• DOI: 10.1134/S0026261723603949

A novel isolate of aerobic, mildly acidophilic methanotrophic bacteria, strain RX1 T , was obtained from a subarctic Sphagnum peat bog in European Russia. Strain RX1 T was represented by highly polymorphic, gram-negative, non-motile, encapsulated cells that possessed a particulate methane monooxygenase enzyme and grew on methane, methanol and acetate. Electron microscopy of ultrathin cell sections revealed stacks of intracytoplasmic membrane vesicles located on one side of a cell as characteristic for methanotrophs of the genus Methylocapsa . Strain RX1 T was capable of fixing dinitrogen, belonged to the family Beijerinckiaceae, and was most closely related to the obligate methanotroph Methylocapsa acidiphila B2 T (98.8% 16S rRNA gene sequence similarity and 92.2% of PmoA sequence identity). The genome of strain RX1 T consisted of a 4.02 Mb chromosome and a 291 kb plasmid, and contained one rrn operon, one pmoCAB operon and about 3800 protein-coding genes. The average nucleotide identity between the genomes of strain RX1 T and M. acidiphila B2 T was 80.0%. Based on the distinct cell morphology, phenotypic and genotypic differences between strain RX T and earlier described members of the genus Methylocapsa , we propose to classify it as representing a novel species of this genus, M. polymorpha , with the type strain RX1 T = VKM B-3754 T = UQM 41806 T .