title: Antipathogenic potential of marine Bacillus sp. SS4 on N-acyl-homoserine-lactone-mediated virulence factors production in Pseudomonas aeruginosa (PAO1).
abstract: Antipathogenic therapy is an outcome of the quorum-sensing inhibition (QSI) mechanism, which targets autoinducer-dependent virulent gene expression in bacterial pathogens. N-acyl homoserine lactone (AHL) acts as a key regulator in the production of virulence factors and biofilm formation in Pseudomonas aeruginosa PAO1 and violacein pigment production in Chromobacterium violaceum. In the present study, the marine bacterial strain SS4 showed potential QSI activity in a concentration-dependent manner (0.5-2 mg/ml) against the AHL-mediated violacein production in C. violaceum (33-86%) and biofilm formation (33-88%), total protease (20-65%), LasA protease (59-68%), LasB elastase (36-68%), pyocyanin (17-86%) and pyoverdin productions in PAO1. The light and confocal laser scanning microscopic analyses confirmed the reduction of the biofilm-forming ability of PAO1 when treated with SS4 extract. Furthermore, the antibiofilm potential was confirmed through static biofilm ring assay, in which ethyl acetate extract of SS4 showed concentration-dependent reduction in the biofilm-forming ability of PAO1. Thus, the result of this study clearly reveals the antipathogenic and antibiofilm properties of the bacterial isolate SS4. Through 16S rDNA analysis, the strain SS4 was identified as Bacillus sp. (GenBank Accession Number: GU471751).
authors: Department of Biotechnology, Alagappa University, Karaikudi 630 003, India.
authors: K Syed
authors: KS
authors: Musthafa
authors: V
authors: V
authors: Saroja
authors: S Karutha
authors: SK
authors: Pandian
authors: A Veera
authors: AV
authors: Ravi
mesh_terms: D001407:Bacillus / Q000235:genetics / Q000472:pathogenicity*; D001426:Bacterial Proteins / Q000378:metabolism; D001483:Base Sequence; D018441:Biofilms / Q000187:drug effects; D002861:Chromobacterium / Q000378:metabolism*; D004275:DNA, Ribosomal / Q000235:genetics; D007211:Indoles / Q000378:metabolism; D008666:Metalloendopeptidases / Q000378:metabolism; D018613:Microscopy, Confocal; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000378:metabolism; D010447:Peptide Hydrolases / Q000378:metabolism; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D011710:Pyocyanine / Q000378:metabolism; D053038:Quorum Sensing / Q000502:physiology*; D017422:Sequence Analysis, DNA
chemical_list: D001426:Bacterial Proteins; D004275:DNA, Ribosomal; D007211:Indoles; D009842:Oligopeptides; C042453:pyoverdin; D011710:Pyocyanine; D010447:Peptide Hydrolases; D008666:Metalloendopeptidases; C043859:pseudolysin, Pseudomonas aeruginosa; C063155:violacein