Cd. Oconnor et al., THE PROTEOME OF SALMONELLA-ENTERICA SEROVAR TYPHIMURIUM - CURRENT PROGRESS ON ITS DETERMINATION AND SOME APPLICATIONS, Electrophoresis, 18(8), 1997, pp. 1483-1490
Salmonella typhimurium (official designation Salmonella enterica serov
ar Typhimurium) is an enteric pathogen and a principal cause of gastro
enteritis in humans. A comprehensive description of the proteins of Sa
lmonella and their patterns of expression under different environmenta
l conditions would greatly increase our understanding of the virulence
of this organism at the molecular level and provide insights into man
y other aspects of Salmonella biology. While a variety of two-dimensio
nal studies of Salmonella have been previously carried out to address
specific questions, little systematic information is available at the
protein level on the numbers of Salmonella polypeptides that have homo
logues in other organisms, their abundance, and the frequency of postt
ranslational modifications. To test the feasibility of determining the
proteome of Salmonella, the identities of 53 randomly sequenced cell
envelope proteins have been determined by N-terminal sequencing of spo
ts from two-dimensional gels. In addition to confirming the existence
of previously hypothetical proteins predicted from genomic sequencing
projects, we found that approximately 20% of the proteins had no match
es in sequence databases. The results suggest that proteome anlysis is
an efficient way to identify novel proteins from prokaryotes and that
the analysis provides a useful approach to the study of Salmonella vi
rulence.