Anti-vibriosis bioactive molecules from marine-derived variant sp. ZZ741A.

The infection of is an important cause of huge economic losses in aquaculture industry. At present, antibiotics are mainly used to prevent and reduce the infection of the , which has accelerated the emergence of multi-drug-resistant strains. New generation alternative anti- drugs were in urgent to solve this problem. In this study, six compounds () were isolated from the sp. ZZ741A, a marine-derived variant, including one new compound, 2-carbamoylphenyl isobutyrate (), five known ones, nocardamine (), dehydroxynocardamine (), phenylacetic acid (), thiophenol () and 2,3-dihydroxybenzoic acid (). The antivibriosis assay showed that compounds and had specific inhibition activity against , , and with the MIC values ranging from 8 to 128 μg/mL. The molecular docking study of their possible mechanism of anti-vibriosis activity showed that the activity might come from the inhibition of Outer membrane protein U (OmpU).