Antimicrobial properties of cultivable bacteria associated with seaweeds in the Gulf of Mannar on the southeast coast of India.

Publisher: Canadian Science Publishing Country of Publication: Canada NLM ID: 0372707 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1480-3275 (Electronic) Linking ISSN: 00084166 NLM ISO Abbreviation: Can J Microbiol Subsets: MEDLINE

Publication: 2011- : Ottawa, ON : Canadian Science Publishing
Original Publication: Ottawa, Canada : National Research Council, [1954-

Anti-Infective Agents/*metabolism ; Bacteria/*metabolism ; Proteobacteria/*metabolism ; Seaweed/*microbiology; Bacteria/genetics ; Bacteria/isolation & purification ; India ; Ligases/isolation & purification ; Ligases/metabolism ; Phylogeny ; Proteobacteria/genetics ; Proteobacteria/isolation & purification ; Seaweed/isolation & purification

In this study, 234 bacterial strains were isolated from 7 seaweed species in the Gulf of Mannar on the southeast coast of India. The strains having consistent antimicrobial activity were chosen for further studies, and this constituted about 9.8% of the active strains isolated. Phylogenetic analysis using 16S rDNA sequencing with the help of classical biochemical identification indicated the existence of 2 major phyla, Firmicutes and Proteobacteria. Antimicrobial activity analysis combined with the results of amplifying genes encoding for polyketide synthetase and nonribosomal peptide synthetase showed that seaweed-associated bacteria had broad-spectrum antimicrobial activity. These epibionts might be beneficial to seaweeds by limiting or preventing the development of competing or fouling bacteria. Phylogenetic analysis of ketosynthase (KS) regions with respect to the diverse range of KS domains showed that the KS domains from the candidate isolates were of Type I. The bacterial cultures retained their antimicrobial activities after plasmid curing, which further suggested that the antimicrobial activity of these isolates was not encoded by plasmid, and the genes encoding the antimicrobial product might be present within the genome. Seaweed-associated bacteria with potential antimicrobial activity suggested that the seaweed species are an ideal ecological niche harboring specific bacterial diversity representing a largely underexplored source of antimicrobial secondary metabolites.

Keywords: algues; antibacterial activity; bactéries marines; marine bacteria; nonribosomal peptide synthetase; peptides non ribosomiques synthétase; polycétide synthétase; polyketide synthetase; seaweed; une activité antibactérienne

0 (Anti-Infective Agents)
EC 6.- (Ligases)

Date Created: 20160705 Date Completed: 20161229 Latest Revision: 20181202

20240628

10.1139/cjm-2015-0769

27374804