Outlook of fosmid library from metagenomic of the symbionts associated with coral Siderastrea stellata: structural and functional screening for metabolic and antimicrobial activity

Abstract

Microorganisms colonize the corals and produce compounds with interesting biological properties for biotechnology. The aim of the present study was to search for biocompounds with industrial potential through the cloning metagenomic DNA of symbionts the coral S. stellata in fosmid vector. The metagenomic library was analyzed using functional screening and sequencing via the Illumina MiSeq. Of the 3648 clones, eight were identified as proteolytic and six as amylolytic. The proteolytic clone, P07H3, also exhibited antimicrobial activity against S. aureus, S Enterica PT11, S Enterica PT4 and S Typhi. No clones were positive for lipase/esterase. Beta-lactamase was a single subsystem identified by Rapid Annotation using Subsystem Technology (RAST) through fosmid sequencing of clone P07H3. However, there were identifications of enzymes that participate in metabolic processes such as polysaccharide catabolism, oxidation-reduction, signal transduction and phosphorylation. When the hypothetical proteins were re-analyzed they exhibited a defined functional domain. All the identified open reading frames (ORFs) had low identity with proteins deposited in BLASTp. The sequencing shows that most of the genomic fragments of clone P07H3 possibly consist of new proteins. The Proteobacteria phylum had the greatest predominance among the analyzed fragments. This is the first report on the prospection of amylases, proteases and antimicrobials of coral S. stellata samples. The analyzes of this study help to improve the knowledge about the metabolic diversity of S. stellata still little explored and viable in the future study of the identified compounds.