Characterization of extracellular proteins produced by Aeromonas hydrophila AH-1.
Aeromonas hydrophila is a ubiquitous Gram-negative bacterium which can cause motile aeromonad septicemia in both fish and humans. A. hydrophila secretes many extracellular proteins associated with pathogenicity and environmental adaptability. In this study, an extracellular proteome map of A. hydrophila AH-1 was constructed. The major extracellular virulence factors were characterized by comparing the proteomes of various deletion mutants with that of the wild type. The results suggested that serine protease was involved in the processing of a toxin and secreted enzymes such as hemolysin, glycerophospholipid-cholesterol acyltransferase and metalloprotease. We also showed that expressions of polar and lateral flagellins were under the control of temperature, FlhA, LafK, and RpoN. In addition, three novel proteins (potential effector proteins including one ExoT-like protein) were revealed to be secreted via the type III secretion system (TTSS) of A. hydrophila AH-1. Another novel finding was the demonstration of a crosstalk between the lateral flagellar system and the TTSS in A. hydrophila. These results showed that proteomics is a powerful tool for characterizing virulence factors. The construction of proteome maps will provide a valuable means of finding potential candidates for developing suitable diagnostics and therapeutics for this emerging pathogen.
Yu
Hong Bing
HB
Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, Singapore.
Kaur
Rasvinder
R
Lim
Simin
S
Wang
Xian Hui
XH
Leung
Ka Yin
KY
D016980:Aeromonas hydrophila / Q000737:chemistry* / Q000235:genetics / Q000472:pathogenicity; D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000737:chemistry* / Q000235:genetics; D020543:Proteome / Q000096:biosynthesis* / Q000737:chemistry* / Q000235:genetics; D037521:Virulence Factors / Q000096:biosynthesis* / Q000737:chemistry* / Q000235:genetics
D001426:Bacterial Proteins; D020543:Proteome; D037521:Virulence Factors