Comprehensive proteomic analysis of Shigella flexneri 2a membrane proteins.
Shigella flexneri is the causative agent of most shigellosis cases in developing countries. We used different proteolytic enzymes to selectively shave the protruding proteins on the surface of purified bacterial membrane sheets or vesicles, and recovered peptides were subsequently identified using 2-D LC-MS/MS. As a result, a total of 666 proteins were unambiguously assigned, including 159 integral membrane proteins, 35 outer membrane proteins and 114 proteins previously annotated as hypothetical. The former had an average grand average hydrophobicity score of 0.362 and were predicted to separate within a pH range of 4.1-10.6 with molecular mass 8-148 kDa, which represents the largest validated set of integral membrane proteins in this organism to date. A functional classification revealed that a large proportion of the identified proteins were involved in cell envelope biogenesis and energy production and conversion. For the first time, this work provides a global view of the S. flexneri 2a membrane subproteome.
Wei
Candong
C
State Key Laboratory for Molecular Virology and Genetic Engineering, Institute of Pathogen Biology, CAMS, Beijing 100730, Peoples Republic of China.
Yang
Jian
J
Zhu
Junping
J
Zhang
Xiaobing
X
Leng
Wenchuan
W
Wang
Jing
J
Xue
Ying
Y
Sun
Lilian
L
Li
Weijun
W
Wang
Jin
J
Jin
Qi
Q
D001425:Bacterial Outer Membrane Proteins / Q000032:analysis*; D002853:Chromatography, Liquid; D015180:Electrophoresis, Gel, Two-Dimensional; D013058:Mass Spectrometry; D008565:Membrane Proteins / Q000032:analysis*; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D020543:Proteome / Q000032:analysis*; D012763:Shigella flexneri / Q000737:chemistry* / Q000166:cytology / Q000235:genetics
D001425:Bacterial Outer Membrane Proteins; D008565:Membrane Proteins; D020543:Proteome