Isolation, identification and screening of microorganisms for cytotoxic activities from deep sea sediments at different pacific stations

摘要

Bacteria and fungi were recovered from deep-sea sediments of the Middle Pacific, West Pacific, and East Pacific by using different isolation media. More than 150 strains were isolated, 90 of which were selected for initial identification and cytotoxic activity tests. The strains were identified by 16S rRNA gene sequencing and grouped into 19 different genera, including Acinetobacter, Arthrobacter, Bacillus, Burkholderia, Halomonas, Hyphomicrobium, Kocuria, Marinobacter, Microbacterium, Micrococcus, Nocardiopsis, Phialocephala, Planomicrobium, Planococcus, Leifsonia, Pseudoalteromonas, Pseudomonas, Psychrobacter, Shewanella, and Streptomyces. The cytotoxicities of the strains toward the mouse temperature-sensitive p34cdc2 mutant tsFT210, murine lymphoma P388 and human leukemia K562 cell lines were determined preliminarily by the sulforhodamine-B (SRB) or methyl thiazolyl tetrazolium (MTT) bioassay method. The metabolites from three bacteria (Bacillus sp. EP39, Pseudomonas sp. WP133, and Pseudomonas sp. WP168) and one fungus (Phialocephala sp. FL30r) had strong cytotoxic activities (Inhibition rate > 50%). Nine cytotoxic compounds belonging to phenazine, indole, polyether, and ester were isolated from them through bioassay-guided chromatography and identified by spectral methods.