Valinomycin biosynthetic gene cluster in Streptomyces: conservation, ecology and evolution

• Published in: PloS one Vol. 4; no. 9; p. e7194
• Main Authors: Matter, Andrea M, Hoot, Sara B, Anderson, Patrick D, Neves, Susana S, Cheng, Yi-Qiang
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 29.09.2009; Public Library of Science (PLoS)
• Subjects: Anti-Bacterial Agents - chemistry; Anti-Bacterial Agents - metabolism; Antibiotics; Bacillus cereus - metabolism; Bacteria; Bayes Theorem; Bioinformatics; Biological Evolution; Biosynthesis; Cereulide; Clusters; Conservation; Cyanobacteria; Deoxyribonucleic acid; Disease transmission; Dissertations & theses; DNA; DNA biosynthesis; DNA sequencing; Ecology; Evolution; Evolutionary biology; Evolutionary Biology/Microbial Evolution and Genomics; Evolutionary conservation; Gene clusters; Gene sequencing; Gene transfer; Gene Transfer, Horizontal; Genes; Genetic distance; Genetic research; Geographical distribution; Ligases; Likelihood Functions; Microbiology/Environmental Microbiology; Microbiology/Microbial Evolution and Genomics; Microbiology/Microbial Physiology and Metabolism; Multigene Family; Natural products; Nucleotide sequence; Oryza; Peptide Synthases - metabolism; Phylogenetics; Phylogeny; Polymerase Chain Reaction; RNA polymerase; RNA, Ribosomal, 16S - metabolism; rRNA 16S; Sequence Analysis, DNA; Streptomyces; Streptomyces - genetics; Streptomyces - metabolism; Valinomycin; Valinomycin - chemistry; Valinomycin - metabolism; United States > US; Wisconsin
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0007194

Many Streptomyces strains are known to produce valinomycin (VLM) antibiotic and the VLM biosynthetic gene cluster (vlm) has been characterized in two independent isolates. Here we report the phylogenetic relationships of these strains using both parsimony and likelihood methods, and discuss whether the vlm gene cluster shows evidence of horizontal transmission common in natural product biosynthetic genes. Eight Streptomyces strains from around the world were obtained and sequenced for three regions of the two large nonribosomal peptide synthetase genes (vlm1 and vlm2) involved in VLM biosynthesis. The DNA sequences representing the vlm gene cluster are highly conserved among all eight environmental strains. The geographic distribution pattern of these strains and the strict congruence between the trees of the two vlm genes and the housekeeping genes, 16S rDNA and trpB, suggest vertical transmission of the vlm gene cluster in Streptomyces with no evidence of horizontal gene transfer. We also explored the relationship of the sequence of vlm genes to that of the cereulide biosynthetic genes (ces) found in Bacillus cereus and found them highly divergent from each other at DNA level (genetic distance values >or= 95.6%). It is possible that the vlm gene cluster and the ces gene cluster may share a relatively distant common ancestor but these two gene clusters have since evolved independently.