Population Genetic Analysis of Streptomyces albidoflavus Reveals Habitat Barriers to Homologous Recombination in the Diversification of Streptomycetes----中国科学院微生物研究所

科研成果

论文题目:	Population Genetic Analysis of Streptomyces albidoflavus Reveals Habitat Barriers to Homologous Recombination in the Diversification of Streptomycetes
作者:	Cheng Kun# Rong Xiaoying#, Pinto-Tomas Adrian, A., Fernandez-Villalobos Marcela, Murillo-Cruz Catalina, Huang Ying*.
联系作者:
刊物名称:	Applied and Environmental Microbiology
期:	81
卷:	3
页:	966-975
年份:	2015
影响因子:	4.359
论文下载:	http://aem.asm.org/content/81/3/966.long
摘要:	Examining the population structure and the influence of recombination and ecology on microbial populations makes great sense for understanding microbial evolution and speciation. Streptomycetes are a diverse group of bacteria that are widely distributed in nature and a rich source of useful bioactive compounds; however, they are rarely subjected to population genetic investigations. In this study, we applied a five-gene-based multilocus sequence analysis (MLSA) scheme to 41 strains of Streptomyces albidoflavus derived from diverse sources, mainly insects, sea, and soil. Frequent recombination was detected in S. albidoflavus, supported by multiple lines of evidence from the pairwise homoplasy index (Phi(w)) test, phylogenetic discordance, the Shimodaira-Hasegawa (SH) test, and network analysis, underpinning the predominance of homologous recombination within Streptomyces species. A strong habitat signal was also observed in both phylogenetic and Structure 2.3.3 analyses, indicating the importance of ecological difference in shaping the population structure. Moreover, all three habitat-associated groups, particularly the entomic group, demonstrated significantly reduced levels of gene flow with one another, generally revealing habitat barriers to recombination. Therefore, a combined effect of homologous recombination and ecology is inferred for S. albidoflavus, where dynamic evolution is at least partly balanced by the extent that differential distributions of strains among habitats limit genetic exchange. Our study stresses the significance of ecology in microbial speciation and reveals the coexistence of homologous recombination and ecological divergence in the evolution of streptomycetes.