Systematic identification of the subproteome of Escherichia coli cell envelope reveals the interaction network of membrane proteins and membrane-associated peripheral proteins.
Membrane proteins of Gram-negative bacteria are key molecules that interface the cells with the environment. Despite recent proteomic identification of numerous oligomer proteins in the Escherichia coli cell envelope, the protein complex of E. coli membrane proteins and their peripherally associated proteins remain ill-defined. In the current study, we systematically analyze the subproteome of E. coli cell envelope enriched in sarcosine-insoluble fraction (SIF) and sarcosine-soluble fraction (SSF) by using proteomic methodologies. One hundred and four proteins out of 184 spots on 2D electrophoresis gels are identified, which includes 31 outer membrane proteins (OMPs). Importantly, our further proteomic studies reveal a number of previously unrecognized membrane-interacting protein complexes, such as the complex consisting of OmpW and fumarate reductase. This established complete proteomic profile of E. coli envelope also sheds new insight into the function(s) of E. coli outer envelope.
Huang
Chuan-Zhong
CZ
Center for Proteomics, Department of Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian 361005, People's Republic of China. wangpeng@xmu.edu.cn
Lin
Xiang-Min
XM
Wu
Li-Na
LN
Zhang
Dan-Feng
DF
Liu
Dong
D
Wang
San-Ying
SY
Peng
Xuan-Xian
XX
D015153:Blotting, Western; D002462:Cell Membrane / Q000235:genetics*; D019295:Computational Biology; D015180:Electrophoresis, Gel, Two-Dimensional; D004926:Escherichia coli / Q000235:genetics*; D008565:Membrane Proteins / Q000235:genetics*; D040901:Proteomics; D012521:Sarcosine; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D008565:Membrane Proteins; D012521:Sarcosine