The Role of System-Specific Molecular Chaperones in the Maturation of Molybdoenzymes in Bacteria

Figure 5

Phylogenetic tree of XdhC homologues. Protein phylogeny of XdhC homologues based on a full length sequence alignment. The tree was constructed by the neighbor-joining method from a matrix of estimated numbers of amino acid substitutions per site calculated with the Dayhoff option of Phylip. Numbers near branches indicate the bootstrap proportion for 100 replicas using the same method. The scale bar indicates 0.1 substitutions per site. Bacterial XdhC homologues from (partially) characterized operons are marked in red, XdhC homologues from Archaea are marked in blue, and in case several XdhC homologues present in one genome, they are marked by H1, H2, H3; class: b: Bacilli; c: Clostridia; α: Alphaproteobacteria; β: Betaproteobacteria; γ: Gammaproteobacteria; δ: Deltaproteobacteria; Act: Actinobacteria; fla: Flavobacteria; Halo: Halobacteria; Ther: Thermoprotei. Underlined XdhC homologues are part of an operon encoding Moco biosynthesis proteins, XdhC homologues in bold are part of an operon encoding a molybdoenzyme, putative molybdoenzyme partners were annotated based on a full length sequence alignment of the Moco binding subunit and by comparison of active site amino acids: PaoC homologues (filled square), XOR homologues (open square), CoxL/CutL homologues (filled star), isoquinoline 1-oxidoreductase homologues (filled circle) and quinaldine 4-oxidase (filled diamond).