Genomic Insights into Denitrifying Methane-Oxidizing Bacteria Gemmobacter fulva sp. Nov., Isolated from an Anabaena Culture.

The genus Gemmobacter grows phototrophically, aerobically, or anaerobically, and utilizes methylated amine. Here, we present two high-quality complete genomes of the strains con4 and con5 T isolated from a culture of Anabaena . The strains possess sMMO (soluble methane monooxygenase)-oxidizing alkanes to carbon dioxide. Functional genes for methane-oxidation ( prmAC , mimBD , adh , gfa , fdh ) were identified. The genome of strain con5 T contains nirB , nirK , nirQ , norB , norC , and norG genes involved in dissimilatory nitrate reduction. The presence of nitrite reductase gene ( nirK ) and the nitric-oxide reductase gene ( norB ) indicates that it could potentially use nitrite as an electron acceptor in anoxic environments. Taxonomic investigations were also performed on two strains through polyphasic methods, proposing two isolates as a novel species of the genus Gemmobacter . The findings obtained through the whole genome analyses provide genome-based evidence of complete oxidation of methane to carbon dioxide. This study provides a genetic blueprint of Gemmobacter   fulva con5 T and its biochemical characteristics, which help us to understand the evolutionary biology of the genus Gemmobacter .