SCREENING AND IDENTIFICATION OF VIBRIO-ANTAGONISTIC BACTERIA FROM THE GASTROINTESTINAL TRACT OF PSEUDOSCIAENA CROCEA
来自大黄鱼(Pseudosciaena crocea)肠道的弧菌拮抗菌的筛选与鉴定

One hundred and fifteen strains of bacteria were isolated from the gastrointestinal tract of cultured, healthy Pseudosciaena crocea and examined for their antagonistic activities against pathogenic Vibrio parahaemolyticus (Vp-1.2164) and Vibrio alginolyticus (Va-Y) by the dot-inoculating method. Three strains of bacteria (X1402-1, X1108 and X3914) inhibited the growth of the pathogenic vibrios. Strain X1402-1 showed the strongest antagonistic activity, with the diameters of inhibition zones of Vp-1.2164 and Va-Y being 28.5mm and 8.7mm, respectively. The diameters of inhibition zones of Vp-1.2164 and Va-Y were 12.0 and 9.0mm, respectively, for strain of X1108, and 0 and 7.2mm, respectively for strain X3914. In addition, their antibacterial spectra were studied. Strain X1402-1 showed the widest antibacterial spectra, inhibiting the growth of 16 out of the 21 strains of bacteria tested. Furthermore, identification of X1402-1, X1108 and X3914 was performed by two methods. With the VITEK-32 Bacteria Identification System (Biomerieux Company), X1402-1, X1108 and X3914 were recognized as Pseudomonas aeruginosa, Pseudomonas putida, and Bacillus licheniformis, respectively; their similarities were 99%. Complementally, the results of 16S rRNA gene sequence analysis showed that nucleotide homology of these three antagonistic strains to Pseudomonas pseudoalcaligenes (EU419918), Pseudomonas putida (FJ440105), and Bacillus licheniformis (DQ988136) were 100.0%, 97.5% and 99.0%, respectively. In summary, strains of X1402-1, X1108 and X3914 were concluded to be Pseudomonas pseudoalcaligenes, Pseudomonas putida and Bacillus licheniformis, respectively.