A selective medium and a specific probe for detection of Vibrio vulnificus

A selective medium (VVM) and a specific 16S rRNA gene (rDNA) probe (V3VV) f or the detection of Vibrio vulnificus were developed. The medium contains D -(+)-cellobiose as the main carbon source and electrolytes (MgCl2-6H(2)O an d KCl), which stimulate bacterial growth. Polymyxin B, colistin, and modera te alkalinity and salinity provide selectivity properties. V. vulnificus gr ows on VVM as flat, bright yellow colonies. Other Vibrio species tested eit her did not grow or showed green-bluish colonies, with the exception of V. campbelli, V. carchariae, and V. navarrensis. There is a higher colony coun t on VVM agar than on cellobiose-colistin agar or on modified cellobiose-po lymyxin B-colistin agar. The specific probe was evaluated by colony hybridi zation and dot blot hybridization with PCR-amplified 16S rDNA using collect ion strains and environmental isolates. No strain studied other than V. vul nificus showed positive hybridization with this oligonucleotide. The combin ed use of VVM agar and the V3VV probe provided the recovery of V. vulnificu s from mixed bacterial suspensions and spiked mussels.