Composition map and functional annotation of xox and lanM clusters. (A) the organization of the MxaFI and XoxF systems of different classes. Genes encoding structural proteins are represented by pink arrows, while auxiliary genes involved in MDH assembly are shown as blue arrows, and regulatory genes are indicated by green arrows. Genes related to methanol metabolism are depicted in various colors. Genes encoding proteins with known or predicted functions unrelated to methanol metabolism are shown in light brown, and the unknown gene is represented in orange. Gene sizes and intergenic regions are not to scale. TonB, tonb-like uptake system; CytC, cytochrome c; cox, cytochrome c oxidase; CtaG, cytochrome c oxidase assembly factor; FQR, putative formaldehyde: Quinone reductase; GAF, GAF-modulated sigma 54-specific transcriptional regulator; GGDEF, diguanylate cyclase; TPR, tetratricopeptide repeat protein; Crp, cyclic AMP-receiving transcriptional regulator; PhoH, PhoH family protein. Species: M. Extorquens, Methylobacterium extorquens AM1; M. Oxyfera, Candidatus “Methylomirabilis oxyfera”; M. Silvestris, Methylocella silvestris BL2; M. Mobilis, Methylotenera mobilis JLW8. More MDH genome information has been published previously [21]. The gene clusters were mapped using ChiPlot (https://www.chiplot.online/gene_cluster.html). (B) Characterization of the lut/lan cluster (MexAM1_META1p1778 to MexAM1_META1p1787). Gene a encodes an SBP transporter, while gene B may encode a group of enzymes that contain carboxylic acid residues adjacent to tryptophan residues in their homologous models. Genes D and G are potentially linked to system function; genes E and F encode components of the ABC transport system; gene H encodes a TonB-dependent receptor protein, and the gray arrows represent unidentified genes. Adapted from [18, 33–35].