Insight into the genetic diversity, resistance, and virulence ofListeriafrom the marine environment: reveal the risk of hypervirulent isolates

Abstract

AbstractListeria monocytogenes is a major human foodborne pathogen and a ubiquitous environmental saprophyte. In this study, we investigated the prevalence and characteristics ofListeria spp. from beach sand in the coastal environment. Three differentListeria spp.,Listeria monocytogenes(n=16),Listeria fleishmanii(n=7), andListeria aquatica(n=3) were isolated from 769 beach sand samples and demonstrated diverse biofilm forming capacity. TheL. monocytogenesisolates belonged to four distinct sequence types (ST87, ST121, ST35, and ST85) and contained the majority of virulence genes, some isolates were hypervirulent clones or had close phylogenetic relatedness with clinical cases. The ST87 isolates showed higher ability of biofilm formation in seawater than other STs strains. As a reservoir of microbes from marine environments and human/animal excrement, coastal sand would play an important role in the spread ofL. monocytogenes and is an environmental risk for human listeriosis.