AIM: To screen the immunogenic membrane proteins ofShigella flexneri 2a 2457T.METHODS: The routine two-dimensional polyacrylamidegel electrophoresis (2-DE) and Western blotting werecombined to screen immunogenic prote...AIM: To screen the immunogenic membrane proteins ofShigella flexneri 2a 2457T.METHODS: The routine two-dimensional polyacrylamidegel electrophoresis (2-DE) and Western blotting werecombined to screen immunogenic proteins of S. flexneri2a 2457T. Serum was gained from rabbits immunizedwith the same bacteria. Immunogenic spots werecut out from the polyacrylamide gel and digested bytrypsin in-gel. Matrix-assisted laser desorption/ionizationtime of flight-mass spectrometry (MALDI-TOF-MS)was performed to determine the molecular weight ofpeptides. Electrospray ionization (ESI-MS/MS) wasperformed to determine the sequences of the interestingpeptides.RESULTS: A total of 20 spots were successfullyidentified from Coomassie brilliant blue stained gelsrepresenting 13 protein entries, 5 known antigens and8 novel antigens. A hypothetical protein (YaeT) wasdetected, which might be a candidate target of vaccine.CONCLUSION: Membrane proteins of S. flexneri 2a2457T were successfully observed by 2-DE. Severalknown and novel antigens were identified by massspectrum.展开更多
Shigella flexneri is an infectious pathogen that causes dysentery to human, which remains a serious threat to public health, particularly in developing countries. In this study, the global protein expression patterns ...Shigella flexneri is an infectious pathogen that causes dysentery to human, which remains a serious threat to public health, particularly in developing countries. In this study, the global protein expression patterns of S. flexneri during transition from exponential growth to stationary phase in vitro were analyzed by using 2-D PAGE combined with MALDI-TOF MS. In a time-course experiment with five time points, the relative abundance of 49 protein spots varied significantly. Interestingly, a putative outer membrane protein YciD （OmpW） was almost not detected in the exponential growth phase but became one of the most abundant proteins in the whole stationary-phase proteome. Some proteins regulated by the global regulator FNR were also significantly induced （such as AnsB, AspA, FrdAB, and KatG） or repressed （such as AceEF, OmpX, SodA, and SucAB） during the growth phase transition. These proteins may be the key effectors of the bacterial cell cycle or play important roles in the cellular maintenance and stress responses. Our expression profile data provide valuable information for the study of bacterial physiology and form the basis for future proteomic analyses of this pathogen.展开更多
基金Supported by the Capital "248" Key Innovation Project, No. H010210360119, State Basic Research Development Program of China No. 973 Program, G1999054103 and 2005CB22904 and National Natural Science Foundation of China No. 30470101
文摘AIM: To screen the immunogenic membrane proteins ofShigella flexneri 2a 2457T.METHODS: The routine two-dimensional polyacrylamidegel electrophoresis (2-DE) and Western blotting werecombined to screen immunogenic proteins of S. flexneri2a 2457T. Serum was gained from rabbits immunizedwith the same bacteria. Immunogenic spots werecut out from the polyacrylamide gel and digested bytrypsin in-gel. Matrix-assisted laser desorption/ionizationtime of flight-mass spectrometry (MALDI-TOF-MS)was performed to determine the molecular weight ofpeptides. Electrospray ionization (ESI-MS/MS) wasperformed to determine the sequences of the interestingpeptides.RESULTS: A total of 20 spots were successfullyidentified from Coomassie brilliant blue stained gelsrepresenting 13 protein entries, 5 known antigens and8 novel antigens. A hypothetical protein (YaeT) wasdetected, which might be a candidate target of vaccine.CONCLUSION: Membrane proteins of S. flexneri 2a2457T were successfully observed by 2-DE. Severalknown and novel antigens were identified by massspectrum.
基金This work was supported by the National Key Basic Research Program of China （973 Program, No. 2005CB522904） the National Natural Science Foundation of China （No. 30470101）.
文摘Shigella flexneri is an infectious pathogen that causes dysentery to human, which remains a serious threat to public health, particularly in developing countries. In this study, the global protein expression patterns of S. flexneri during transition from exponential growth to stationary phase in vitro were analyzed by using 2-D PAGE combined with MALDI-TOF MS. In a time-course experiment with five time points, the relative abundance of 49 protein spots varied significantly. Interestingly, a putative outer membrane protein YciD （OmpW） was almost not detected in the exponential growth phase but became one of the most abundant proteins in the whole stationary-phase proteome. Some proteins regulated by the global regulator FNR were also significantly induced （such as AnsB, AspA, FrdAB, and KatG） or repressed （such as AceEF, OmpX, SodA, and SucAB） during the growth phase transition. These proteins may be the key effectors of the bacterial cell cycle or play important roles in the cellular maintenance and stress responses. Our expression profile data provide valuable information for the study of bacterial physiology and form the basis for future proteomic analyses of this pathogen.
