Genome mining of Salinispora sp strains isolated from the São Pedro and São Paulo Archipelago in Brazil

Studies on marine microorganisms have benefited from the development of DNA sequencing technology combined with bioinformatics-based approaches to the discovery of new secondary metabolites. The genus Salinispora, with a wide geographical distribution, has great potential for the production of secondary metabolites. This genus was recently detected on the coast of Brazil, in the São Pedro and São Paulo archipelago (SPSPA), located on Atlantic Ocean approximately 1,000 km from the continental Brazilian coast (N00º 55.1'  W29º 20.7'). The aim of this study was to explore four new strains (BRA-172, BRA-190, BRA-258 and BRA-201) isolated from SPSPA and characterize their potential for the production of new compounds using genome mining. The 16S RNA sequence identified strain BRA-201 as S. pacifica (e.g. CNS 863), while all other strains were identified as S. arenicola (e.g. CNS 205). Further, genome sequencing of the strains BRA-201, 172 and 258 revealed genome sizes ranging from 6.5 to 7.5MB and analysis using antiSMASH and NaPDoS identified 21-23 gene clusters in each of the strains supporting diverse biosynthetic pathway, including specifically salinosporamide, rifamycin, lymphostin and siderophore related pathways. Although the strains from Brazil do not contain any new gene clusters until now, they have a different subset of clusters as compared with characterized Salinispora strains from elsewhere. Since only a few Salinispora clusters have been chemically characterized to date, we are using molecular network analysis of the extracts to improve the characterization of the strains.