title: Stigmatellin Y - An anti-biofilm compound from Bacillus subtilis BR4 possibly interferes in PQS-PqsR mediated quorum sensing system in Pseudomonas aeruginosa.
abstract: Hitherto this is the first report pertaining to production of biofilm inhibitory compound(s) (BIC) from Bacillus subtilis BR4 against Pseudomonas aeruginosa (ATCC 27853) coupled with production optimization. In order to achieve this, combinations of media components were formulated by employing statistical tools such as Plackett-Burman analysis and central composite rotatable design (CCRD). It was evident that at 35mlL-1glycerol and 3.8gL-1casamino acid, anti-biofilm activity and production of extracellular protein significantly increased by 1.5-fold and 1.2-fold, respectively. These results corroborate that the combination of glycerol and casamino acid plays a key role in the production of BIC. Further, metabolic profiling of BIC was carried out using liquid chromatography/tandem mass spectrometry (LC-MS/MS) based on m/z value. The presence of Stigmatellin Y was predicted with monoisotopic neutral mass of 484.2825Da. In support of optimization study, higher production of BIC was confirmed in the optimized-media-grown BR4 (OPT-BR4) than in the ideal-media-grown BR4 (ID-BR4) by LC-MS/MS analysis. PqsR in P. aeruginosa is a potential target for anti-virulent therapy. Molecular docking study has revealed that Stigmatellin Y interacts with PqsR in the similar orientation like a cognate signal (PQS) and synthetic inhibitor. In addition, Stigmatellin Y was found to exhibit interaction with four more amino acid residues of PqsR to establish strong affinity. Stigmatellin Y thus might play a role of competitor for PQS to distract PQS-PqsR mediated communication in P. aeruginosa. The present investigation thus paves new avenues to develop anti-Pseudomonas virulent therapy.
authors.affiliation: Department of Molecular Microbiology, School of Biotechnology, Madurai Kamaraj University, Madurai 625021, Tamil Nadu, India.
authors.forename: Seenivasan
authors.initials: S
authors.lastname: Boopathi
authors.affiliation: Bruker Daltonics India (P) Ltd, New Delhi, India.
authors.forename: Rajesh
authors.initials: R
authors.lastname: Vashisth
authors.affiliation: Centre of Excellence in Bioinformatics, School of Biotechnology, Madurai Kamaraj University, Madurai 625021, Tamil Nadu, India.
authors.forename: Prabu
authors.initials: P
authors.lastname: Manoharan
authors.affiliation: Department of Pharmaceutical Technology, Anna University, BIT campus, Trichy 620024, Tamil Nadu, India.
authors.forename: Ruckmani
authors.initials: R
authors.lastname: Kandasamy
authors.affiliation: Department of Molecular Microbiology, School of Biotechnology, Madurai Kamaraj University, Madurai 625021, Tamil Nadu, India. Electronic address: sivamku.ac@gmail.com.
authors.forename: Natesan
authors.initials: N
authors.lastname: Sivakumar
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology; D001412:Bacillus subtilis / Q000737:chemistry* / Q000378:metabolism; D001426:Bacterial Proteins / Q000378:metabolism*; D001665:Binding Sites; D002851:Chromatography, High Pressure Liquid; D008024:Ligands; D062105:Molecular Docking Simulation; D011090:Polyenes / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology; D017434:Protein Structure, Tertiary; D011550:Pseudomonas aeruginosa / Q000502:physiology*; D053038:Quorum Sensing / Q000187:drug effects*; D053719:Tandem Mass Spectrometry
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D008024:Ligands; D011090:Polyenes; C041573:stigmatellin
keywords: Bacillus subtilis; Biofilm; PqsR; Pseudomonas aeruginosa; Stigmatellin Y