RT info:eu-repo/semantics/article T1 Protocol for specific isolation of virulent strains of Vibrio vulnificus serovar E (Biotype 2) from environmental samples A1 Sanjuan Caro, Eva A1 Amaro, Carmen K1 Vibrio vulnificus K1 Pathogenes K1 Human infections AB The eel pathogen Vibrio vulnificus biotype 2 comprises at least three serovars, with serovar E being the onlyone involved in both epizootics of eel vibriosis and sporadic cases of human infections. The virulent strains ofthis serovar (VSE) have only been recovered from clinical (mainly eel tissue) sources. The main objective of thiswork was to design and validate a new protocol for VSE-specific isolation from environmental samples. The keyelement of the new protocol is the broth used for the first step (saline eel serum broth [SEB]), which containseel serum as a nutritive and selective component. This approach takes advantage of the ability of VSE cells togrow in eel serum and thus to separate themselves from the pool of competitors. The growth yield in SEB after8 h of incubation was 1,000 times higher for VSE strains than for their putative competitors (including biotype1 strains of the species). The selective and differential agar Vibrio vulnificus medium (VVM) was selected fromfive selective media for the second step because it gave the highest plating efficiency not only for the VSE groupbut also for other V. vulnificus groups, including biotype 3. The entire protocol was validated by field studies,with alkaline peptone water plus VVM as a control. V. vulnificus was isolated by both protocols, but serovar Ewas only recovered by the new method described here. All selected serovar E isolates were identified as VSEsince they were virulent for both eels and iron-overloaded mice and resisted the bactericidal action of eel andiron-overloaded human sera. In conclusion, this new protocol is a suitable method for the isolation of VSE strainsfrom environmental samples and is recommended for epidemiological studies of the pathogenic serovar E. SN 1098-5336 YR 2004 FD 2004 LK http://riull.ull.es/xmlui/handle/915/35662 UL http://riull.ull.es/xmlui/handle/915/35662 LA en DS Repositorio institucional de la Universidad de La Laguna RD 22-may-2024