Establishment of the phylogenetic relationship between the microbial producers of cyclodextrin glucanotransferases using their complete amino acid sequences

A phylogenetic tree was constructed on the basis of the amino acid sequences of the known cyclodextrin glucanotransferases (CDGTs), including those deduced from the nucleotide sequences of Bacillus sp. strain 6.6.3 and Paenibacillus macerans IB-7 genes encoding alpha- and beta-CDGTs. The tree clearly demonstrates the existence of distinct phylogenetic groups of CDGT-producing microorganisms and the divergence of the alpha-, beta-, and gamma-CDGT produced by microorganisms from the genera Bacillus, Paenibacillus, Brevibacillus, and Thermoanaerobacter from a common ancestor, whereas the CDGT of Klebsiella pneumoniae is independent and results from the convergence of different ancestors. The degree of homology of the leader peptide sequences of CDGTs may serve as a criterion of intraspecies relatedness between CDGT-producing microorganisms.