Adhesion Of Pathogenic Vibrio Alginolyticus To Mucus Of Large Yellow Croakers

The physicochemical characteristics of skin, gill and intestinal mucus of large yellow croakers are studied. Adhesion of pathogenic V. alginolyticus to the mucus on different tissues of large yellow croakers with different environmental factors or under starvation condition is evaluated by the method of isotope tracer or the method of counting by microscope. Kinetics of adhesion of V. alginolyticus to different mucus and mechanism involved in the bacterial adherence process were primarily probed, and inhibition of bacterial adhesion by lactic acid and monosaccharides is studied. The results as follows:1. The physicochemical characteristics of mucusBacteriostatic effects of the skin and intestinal mucus of large yellow croakers on pathogenic V. alginolyticus are detected, but not detectable in gill mucus, however, bacteria grow faster in gill and intestinal mucus after incubating for 15h compared to the growth of bacteria in control groups. Lysozyme activity is positive in the skin mucus, but not detectable in other mucus. The level of IgM in skin and gill mucus is higher than that in intestinal mucus. V. alginolyticus can grow by using the mucus as sole carbon source. The different chemical compositions found in different mucus are proved by the profile of SDS-PAGE.2. Kinetics of adhesion of V. alginolyticus to different mucusThe bacterial adhesion to skin, gill and hindgut mucus reached equilibrium after 180min, at which time the number of V. alginolyticus adhered to the mucus approximately up to 7.26×104, 7.57×104, 1.25×105 bacteria·mm-2, respectively, and the bacterial adhesion to foregut mucus reached equilibrium after 150min, at which time the adhesive quantity approximately up to1.33×105 bacteria·mm-2. Hindgut mucus has the highest em and kx, while foregut mucus and skin mucus has the highest and lowest affinity index to V. alginolyticus, respectively.3. Influence of environmental factors on the bacterial adhesionThe bacterial adhesion is influenced remarkably by environmental factors such as...