Open AccessAntibiofilm activity substances derived from coral symbiotic bacterial extract inhibit biofouling by the model strain Pseudomonas aeruginosa PAO 1
Author(s) -
Song Yu,
Cai ZhongHua,
Lao YongMin,
Jin Hui,
Ying KeZhen,
Lin GuangHui,
Zhou Jin
Publication year - 2018
Publication title -
microbial biotechnology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.287
H-Index - 74
ISSN - 1751-7915
DOI - 10.1111/1751-7915.13312
Subject(s) - pseudomonas aeruginosa , coral , biofouling , strain (injury) , microbiology and biotechnology , biofilm , chemistry , pseudomonas , biology , bacteria , biochemistry , ecology , anatomy , membrane , genetics
Summary The mitigation of biofouling has received significant research attention, with particular focus on non‐toxic and sustainable strategies. Here, we investigated quorum sensing inhibitor (QSI) bacteria as a means of controlling biofouling in a laboratory‐scale system. Approximately, 200 strains were isolated from coral ( Pocillopora damicornis ) and screened for their ability to inhibit quorum sensing (QS). Approximately, 15% of the isolates exhibited QSI activity, and a typical coral symbiotic bacterium, H12‐ Vibrio alginolyticus , was selected in order for us to investigate quorum sensing inhibitory activity further. Confocal microscopy revealed that V. alginolyticus extract inhibited biofilm formation from Pseudomonas aeruginosa PAO 1. In addition, the secondary metabolites of V. alginolyticus inhibited PAO 1 virulence phenotypes by downregulating motility ability, elastase activity and rhamnolipid production. NMR and MS spectrometry suggested that the potential bioactive compound involved was rhodamine isothiocyanate. Quantitative real‐time PCR indicated that the bacterial extract induced a significant downregulation of QS regulatory genes ( lasB, lasI, lasR, rhlI, rhlR ) and virulence‐related genes ( pqsA , pqsR ). The possible mechanism underlying the action of rhodamine isothiocyanate analogue involves the disruption of the las and/or rhl system of PAO 1. Our results highlight coral microbes as a bioresource pool for developing QS inhibitors and identifying novel antifouling agents.