Detection and Expression of Biosynthetic Genes in Actinobacteria ...

BERVANAKIS,G.Chapter 3: RESULTSAntibioticsSporePigmentsAntibioticsFigure 24. Unrooted neighbour-joining phylogenetic tree constructed from amino acid sequencesof KSα genes fragments from type II polyketide synthases. The amino acid sequence accessionnumbers for the reference strains are as follows; A. verrucosospora (BAA82309); S. glaucescens(CAA33369); S. nogalater (BAA92283); S. venezuelae (BAA92282); S. halstedii (AAA02833); S.coelicolor whiE (CAA39408); Kibdelosporangium aridum (AAA67433); S. venezuelae (AAB36562);S. griseus (CAA54858); S. nogalater (CAA12017); S. nogalater (BAA92281); S. argillaceus(CAA61989); S. rochei (BAA87907); S. steffisburgenesis (BAA92278); S. platensis (BAA92279); S.rimosus(CAA80985); S. bobili (BAA92272); S. galilaeus (BAA92273); S. capoamus (BAA92274); S.tauricus (BAA92275); S. purpurascens (BAA92276); S .peucetius (AAA65206); S. arenae(AAD20267); S. vioaceoruberTü22 (CAA34369); S. coelicolor (CAA45043); S. roseofulvus(AAA19616) and amplified KSα from the Cerylid isolates A3023 and A1488. The sequences from thereference strains where obtained from GenBank.The amino acid sequences of 24 known antibiotic type II PKS gene fragments and 2spore pigment type II PKS gene fragments were used as a basis for classification ofthe Cerylid isolates. The most clearly separated groups contain genes involved in thebiosynthesis of antibiotics (Figure 24). Another identifiable group is the group that isfrom the spore pigments. Both of the Cerylid isolates A3023 and A1488 have beenplaced on unique branches by the analysis in the spore pigment group. The type IIpolyketide synthase phylogenetic tree also shows that the KS gene amplified fragmentfrom isolates A3023 and A1488 are closely related to each other._____________________________________________________________________81