Identification and antibacterial activity of three mangrove-derived Streptomyces / 中国药理学通报

ABSTRACT

Aim To study and identify the antibacterial activity of three strains of Streptomyces (K57M, K51M, K131M) collected from the roots of mangrove rhizosphere in Maowei Sea, Guangxi. Methods Acti-nobacteria were isolated on four media and purified by ISP2 medium. The 16S rRNA gene sequences of three actinobacteria strains were obtained by PCR amplification and sequencing. Sequences of 16S rRNA gene obtained by PCR amplification were submitted to gene database for BLAST search. Phylogenetic tree was constructed by adjacency method, and homology analysis was carried out to study the diversity and novelty of actinobacteria. Three actinobacteria strains underwent primary screening using Oxford cup method, and the antimicrobial activity of the sample of El-3, AI-3 and Ml-3 received secondary screening using disk diffusion method. Results Sequence alignment analysis of 16S rRNA gene revealed that strain K57M might be a potential new actinobacteria. The results of screening for antimicrobial activity showed that three strains of Streptomyces, K57M, K51M and K131M, had good antimicrobial activities against different drug-sensitive strains. Conclusions Streptomyces from rhizosphere in the roots of mangrove forests in Guangxi can produce strong antibacterial activities, which provides great possibilities to explore natural active antibiotics.