The existence of strains of Vibrio vulnificus serovar E that are avirulent
for eels is reported in this work. These isolates were recovered from water
and oysters and differed from eel virulent strains in (i) fermentation and
utilization of mannitol, (ii) ribotyping after HindIII digestion, and (iii
) susceptibility to eel serum. Lipopolysaccharide of these strains lacked t
he highest molecular weight immunoreactive bands, which are probably involv
ed in serum resistance.