A two‐dimensional proteome map of Shigella flexneri

Abstract

Shigella flexneri is a Gram-negative facultatively intracellular pathogen responsible for bacillary dysentery in humans. In this study, extracellular proteins from the culture medium and whole cell proteins in cellular extracts of S. flexneri 2a strain 2457T were examined by two-dimensional (2-D) gel electrophoresis using immobilized pH gradient (IPG) technology. Proteins were identified by matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) in combination with Mascot search program. In total, among the 488 proteins spots processed, 388 proteins were identified. The identified proteins represented 169 genes. By comparing results of Mascot search against databases of Escherichia coli and genomes of S. flexneri 2a, one S. flexneri-specific protein was identified and one possible gap was found in 2457T genome sequences. Although this proteome map is still incomplete, it is already a useful reference for future studies involving pathogenicity, vaccine development, design of novel antibacterial drugs, etc. Proteome maps and a table of all identified proteins are available on the internet at www.proteomics.com.cn.

A Proteome Reference Map and Proteomic Analysis of Bifidobacterium longum NCC2705

“…Similar results have been reported in other microorganisms (10,11,53). In bifidobacteria, there is evidence for the existence of two distinct F6P phosphoketolase enzymes (34,35): a specific enzyme (F6PPK) solely for F6P found in humans, such as Bifidobacterium dentium, and a dual substrate xylulose-5-phosphate/F6P phosphoketolase (Xfp; pI, 5.0; 92,469 Da) found in animals, such as Bifidobacterium globosum. The dual specificity xylulose 5-phosphate/F6P phosphoketolase is encoded by the gene xfp, which was first described in Bifidobacterium animalis subsp.…”

“…Discrepancies between gel-estimated and theoretical masses might result from post-translational proteolytic processing and modification. These phenomena have been reported in similar studies (34,59). Different from their theoretical pI values, several proteins appeared in the relatively acidic region (such as spots 60, 321, and 525) or in the alkaline region (such as spots 86, 484, and 792).…”

“…It is also one of the best methods of investigating basic biological processes such as pathogenesis, physiology, and metabolic mechanisms (13,14). In recent years 2-D electrophoresis has been used in proteomic studies of many bacteria, including Haemophilus influenzae (15)(16)(17)(18), Mycobacterium tuberculosis (19 -21), Escherichia coli (13,(22)(23)(24), Helicobacter pylori (25,26), Bacillus subtilis (27,28), Mycoplasma pneumoniae (29), Lactococcus lactis (30 -33), Shigella flexneri (34), Agrobacterium tumefaciens (35), Vibrio cholerae (36), and Brucella melitensis (37).…”

Towards the proteome of the marine bacteriumRhodopirellula baltica: Mapping the soluble proteins

“…1). As known from proteomic studies with other bacteria, enzymes of these central pathways belong to the most abundant protein spots on 2-D gels [16,17]. No evidence was obtained for the presence of the Entner-Doudoroff pathway, which agrees with the bioinformatical prediction [4].…”

Two-dimensional gel electrophoresis in bacterial proteomics

“…2-D gel image database (SWISS-2DPAGE) was established in 1993, with the premise of having an internet-accessible resource where all the spots on high quality 2-D gels of an organism's proteome were clearly annotated and identified (Appel et al, 1993 Regula et al, 2000;Cordwell et al, 2002;Liao et al, 2003;Coelho et al, 2004;Eymann et al, 2004;Folio et al, 2004;Rosen et al, 2004;Encheva et al, 2005;Wang et al, 2005;Encheva et al, 2006). Through concerted and exhaustive efforts, it is often possible to resolve and identify more than a thousand protein spots in a comprehensive 2-D reference map.…”