A unique strain of Vibrio harveyi is the causative agent of scale drop and muscle necrosis disease (SDMND) in Asian sea bass (Lates calcarifer). This study investigated the protein profiles of SDMND-causing Vibrio harveyi isolates compared to the reference V. harveyi ATCC 14126 strain. A distinct protein band of 33 kDa, namely HP33, found from only V. harveyi SDMND was subjected to analysis by LC-MS/MS and the identified peptide sequences matched to an unknown hypothetical protein. Detection of HP33 coding sequence was investigated at both genomic and transcriptional levels and the results consistently supported the protein analysis. Recombinant HP33 protein was then produced using Escherichia coli system. The rHP33 protein did not cause mortality or visible clinical signs to Asian sea bass. However, the rHP33 protein was able to stimulate antibody response in Asian sea bass as evidenced by Western blotting and agglutination tests. Here, we proposed that rHP33 might be a good protein target for development of subunit vaccine and/or immunostimulant to protect Asian sea bass from SDMND.

哈维氏弧菌的独特菌株是亚洲鲈鱼（Lates calcarifer）鳞屑减少和肌肉坏死病（SDMND）的病原体。这项研究调查了引起SDMND的哈维弧菌分离株与参考哈维弧菌ATCC 14126菌株相比的蛋白质谱。仅通过哈氏弧菌SDMND发现的33 kDa的独特蛋白带，即HP33，通过LC-MS / MS进行分析，鉴定出的肽序列与未知的假设蛋白相匹配。在基因组和转录水平上都研究了HP33编码序列的检测，结果始终支持蛋白质分析。然后使用大肠杆菌系统。rHP33蛋白不会导致亚洲鲈鱼死亡或出现明显的临床体征。然而，如西方印迹和凝集试验所证实的，rHP33蛋白能够刺激亚洲鲈鱼中的抗体应答。在这里，我们建议rHP33可能是亚基疫苗和/或免疫刺激剂的良好蛋白质靶标，以保护亚洲鲈鱼免受SDMND侵害。