Immunoproteomics of extracellular proteins of the Aeromonas hydrophila China vaccine strain J-1 reveal a highly immunoreactive outer membrane protein.
Aeromonas hydrophila is a gram-negative bacterium that can infect a variety of aquatic and terrestrial animals. It is essential to develop a vaccine to reduce the economic losses caused by this bacterium in aquaculture worldwide. Here, an immunoproteomic assay was used to identify the immunogenic extracellular proteins of the Chinese vaccine strain J-1. Ten unique immunogenic proteins were identified from the two-dimensional electrophoresis immunoblot profiles by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) or MALDI-TOF-TOF-MS. One protein of interest, Omp38, was detected by antisera on two-dimensional immunoblots, suggesting that it might be located both extracellularly and in the membrane. In exploring the potential of Omp38 as a vaccine candidate in fish, we found the omp38 gene to be prevalent by PCR among different (36/48) A. hydrophila isolates. The recombinant Omp38 induced a strong antibody response in rabbits, and the polyclonal antibody could recognize a band of approximately 38 kDa in the immunoblots of outer membrane protein extracts from most (24/40) of the A. hydrophila strains, including different predominant serotypes in China. These results indicated that the outer membrane antigen identified in this study could be developed as a vaccine candidate to induce protective immunity against A. hydrophila infection.
Ni
Xiao-dan
XD
Nanjing Agricultural University, China.
Wang
Na
N
Liu
Yong-jie
YJ
Lu
Cheng-ping
CP
D016980:Aeromonas hydrophila / Q000145:classification / Q000276:immunology* / Q000302:isolation & purification / Q000378:metabolism; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D001428:Bacterial Vaccines; D002681:China; D005393:Fish Diseases / Q000276:immunology / Q000382:microbiology / Q000517:prevention & control; D016905:Gram-Negative Bacterial Infections / Q000276:immunology* / Q000382:microbiology / Q000517:prevention & control; D015151:Immunoblotting; D007123:Immunoelectrophoresis, Two-Dimensional; D020543:Proteome; D040901:Proteomics / Q000379:methods*; D011817:Rabbits; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001428:Bacterial Vaccines; D020543:Proteome; D011994:Recombinant Proteins