title: Quorum sensing-disrupting coumarin suppressing virulence phenotypes in Vibrio splendidus.
abstract: In the present study, the effects of an environmental friendly natural reagent coumarin, on the growth and potential virulence factors, as well as its ability to interfere the infection of Vibrio splendidus (Vs), were determined. Coumarin showed no effects on the maximal growth of Vs, and biofilm formation of Vs, while it significantly decreased protease activity and hemolytic activity by 43 and 80%, respectively. Correspondingly, coumarin exhibited an obviously protective effect, with a relative percent survival of 60% upon Apostichopus japonicus from infection by Vs. To preliminarily investigate the mechanism underlining the inhibitory effects, regulation of genes Vsm and Vsh respectively related to protease activity and hemolytic activity by supernatant and supernatant extract containing acyl-homoserine lactones (AHLs) and coumarin was determined. Cell-free supernatant from higher density and its ethyl acetate extract containing AHL signal molecules could respectively upregulate the mRNA level of Vsm by 17.4- and 2.3-fold and Vsh by 7.2- and 5.0-fold, when Vs was at lower cell density. However, coumarin could reduce the stimulatory effects of both the supernatant and its ethyl acetate extract. Combining all the results in our study, it was suggested that coumarin could be considered as an alternative to be used for controlling infection of Vs, downregulating the expression of potential virulence factors through interfering the AHL-mediated pathways.
authors.affiliation: School of Marine Sciences, Ningbo University, 818 Fenghua Road, Ningbo, Zhejiang Province, 315211, People's Republic of China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Zhang
authors.affiliation: School of Marine Sciences, Ningbo University, 818 Fenghua Road, Ningbo, Zhejiang Province, 315211, People's Republic of China.
authors.forename: Ningning
authors.initials: N
authors.lastname: Liu
authors.affiliation: School of Marine Sciences, Ningbo University, 818 Fenghua Road, Ningbo, Zhejiang Province, 315211, People's Republic of China.
authors.forename: Weikang
authors.initials: W
authors.lastname: Liang
authors.affiliation: School of Marine Sciences, Ningbo University, 818 Fenghua Road, Ningbo, Zhejiang Province, 315211, People's Republic of China.
authors.forename: Qingxi
authors.initials: Q
authors.lastname: Han
authors.affiliation: School of Marine Sciences, Ningbo University, 818 Fenghua Road, Ningbo, Zhejiang Province, 315211, People's Republic of China. zhangweiwei1@nbu.edu.cn.
authors.forename: Weiwei
authors.initials: W
authors.lastname: Zhang
authors.affiliation: School of Marine Sciences, Ningbo University, 818 Fenghua Road, Ningbo, Zhejiang Province, 315211, People's Republic of China. lichenghua@nbu.edu.cn.
authors.forename: Chenghua
authors.initials: C
authors.lastname: Li
mesh_terms: D054742:Acyl-Butyrolactones / Q000494:pharmacology; D000818:Animals; D017756:Aquaculture; D001426:Bacterial Proteins / Q000187:drug effects / Q000235:genetics; D018441:Biofilms / Q000187:drug effects* / Q000254:growth & development; D003374:Coumarins / Q000494:pharmacology*; D003470:Culture Media / Q000737:chemistry; D015536:Down-Regulation; D006461:Hemolysis / Q000187:drug effects; D010447:Peptide Hydrolases / Q000378:metabolism; D010641:Phenotype; D053038:Quorum Sensing / Q000187:drug effects*; D047528:Stichopus / Q000187:drug effects / Q000382:microbiology; D014733:Vibrio / Q000187:drug effects* / Q000254:growth & development / Q000472:pathogenicity*; D014774:Virulence / Q000187:drug effects / Q000235:genetics; D037521:Virulence Factors
chemical_list: D054742:Acyl-Butyrolactones; D001426:Bacterial Proteins; D003374:Coumarins; D003470:Culture Media; D037521:Virulence Factors; D010447:Peptide Hydrolases
keywords: Coumarin; Hemolytic activity; Protease; Protective effect; Vibrio splendidus Vs