Identification and characterization of Aeromonas hydrophila isolated from Micropterus salmoides

One dominant strain of infectious bacteria,named M-1 stain,was isolated from skin wound of Micropterus salmoides with rot body symptom in Guangdong province.Artificial infection experiments showed that healthy Micropterus salmoides appeared similar sign after infected with the bacteria strain.Bacteria morphology,physiology and biochemistry assays were used to identify the isolated bacteria.The characteristics of the M-1 strain was in accordance with those of Aeromonas hydrophila.PCR was performed to identify the bacteria both 16S rRNA gene and hemolysin gene of the M-1 strain possessed high similarity with those of Aeromonas hydrophila registered in GenBank.The strain was furthermore identified to be virulent strains of Aeromonas hydrophila indicated by the result of phylogenetic tree.The diseased Micropterus salmoides with rot body symptom was supposed to be infected by Aeromonas hydrophila.