[Analysis of exoproteins of El Tor Vibrio cholerae by 2DE and MALDI-TOF-MS/MS].
OBJECTIVE
Our aim is to analyze the exoproteins of the epidemic strain and nonepidemic strain of El Tor Vibrio cholerae.


METHODS
We separated the exoproteins of two El Tor strains, one epidemic strain N16961 and one nonepidemic strain 92-3, by two dimension electrophoresis. All protein spots were identified by MALDI-TOF (Matrix Assisted Laser Desorption Ionization-Time of Flight) mass spectrometry and database referencing.


RESULTS
We identified 49 exoproteins from 206 protein spots in epidemic strain and 42 exoproteins from 236 protein spots in nonepidemic strain. Sixty-eight exoproteins were totally identified in two strains, and the proteins with signal peptides were about 55.88% in total. We classified the exoproteins into 10 subgroups according to their functions. Among them were metabolic enzymes, protein maintenance and folding, protein synthesis and signal transduction proteins, which accounted for 36.76% of all the proteins identified. We identified 11 hypothetical proteins and 2 unknown function proteins with signal peptides at the first time, accounting for 19.12%. Transporter, flagellum components, degradation enzymes, outer membrane proteins and toxin accounted for 14.71%, 11.76%, 10.29%, 5.88%, 1.47% separately.


CONCLUSIONS
We obtained the exoprotein profiles of epidemic strain and nonepidemic strain of El Tor Vibrio cholerae. The reasons of why the flagellum components without signal peptides that are associated closely with virulence could be released out of the bacteria, and why with high hemagglutinin/protease secretion in nonepidemic strains should be analyzed in the future.
Yan
Xiaomei
X
National Institute of Infectious Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China. yanxiaomei@icdc.cn
Xiao
Di
D
Zhao
Fei
F
Gu
Yixin
Y
Meng
Fanliang
F
Zhang
Jianzhong
J
D001426:Bacterial Proteins / Q000032:analysis / Q000737:chemistry; D002771:Cholera / Q000382:microbiology*; D030562:Databases, Protein; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods*; D013058:Mass Spectrometry / Q000379:methods; D020543:Proteome / Q000032:analysis; D020539:Sequence Analysis, Protein; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D014734:Vibrio cholerae / Q000737:chemistry / Q000235:genetics / Q000472:pathogenicity*
D001426:Bacterial Proteins; D020543:Proteome