Fig. 7
From: Novel facultative Methylocella strains are active methane consumers at terrestrial natural gas seeps
a Gene operon encoding the propane monooxygenase in Methylocella sp. PC1 and PC4 compared with their homologues in Methylocella silvestris BL2. Names of the genes are given above and amino acid identities to their homologous proteins in Methylocella silvestris BL2 are shown in brackets. b Gene operon putatively encoding butane monooxygenase in Methylocella sp. PC1 and PC4 compared with their homologues in Thauera butanivorans. c Phylogenetic analysis of the alpha subunit of propane monooxygenase (PrmA) and putative butane monooxygenase (BmoX) from Methylocella PC1 and PC4 isolates (red and blue, respectively). PrmA and BmoX from known closely related strains (bold black) and other soluble diiron monooxygenases (ThmA, alpha subunit of tetrahydrofuran monooxygenase; Blr3677 and Rsp2792, putative monooxygenases; PmoC, alpha subunit of propene monooxygenase; MmoX, alpha subunit of methane monooxygenase; DmpN, alpha subunit of phenol hydroxylase; TomA3, alpha subunit of toluene ortho-monooxygenase; IsoA, alpha subunit of isoprene monooxygenase; and TouA, toluene o-xylene monooxygenase component) from different bacteria are also presented. Compressed MmoX sequences are same as the known methane monooxygenases presented in Fig. 5b. Protein names and accession number for the sequences are given in brackets. Amino acid sequences were aligned using Mega 7.0 and the optimal tree (drawn to scale, with branch lengths measured in the number of substitutions per site) with the sum of branch length = 5.7 is shown where the evolutionary history was inferred using the neighbour-joining method (316 positions in the final dataset). The percentage of replicate trees in which the associated taxa clustered together in the bootstrap test (1000 replicates) ranged from 60 to 100