Global Analysis of Brucella melitensis Proteomes

Abstract

Brucella melitensis is a facultative, intracellular, gram-negative cocco-bacillus that causes Malta fever in humans and brucellosis in animals. There are at least six species in the genus, and the disease is classified as zoonotic because several species infect humans. Using 2-D gel electrophoresis and mass spectrometry, we have initiated (i) a comprehensive mapping and identification of all the expressed proteins of B. melitensis virulent strain 16M, and (ii) a comparative study of its proteome with the attentuated vaccinal strain Rev 1. Comprehensive proteome maps of all six Brucella species will be generated in order to obtain vital information for vaccine development, identification of pathogenicity islands, and establishment of host specificity and evolutionary relatedness.

Brucellosis - new aspects of an old disease

“…Recent investigations comparing proteomes of B. melitensis 16M and the vaccine strain, Rev1, have revealed differences in expression of the 31‐kDa immunogenic outer membrane protein, regulatory proteins involved in the acquisition of iron, those utilized for sugar and amino acid binding, lipid degradation (Eschenbrenner et al. 2002; Mujer et al. 2002; Wagner et al.…”

Molecular targets for rapid identification of Brucella spp

“…are due to unique genes or differences in transcription and expression. The information we can obtain from differential expression studies will complement recent research in comparative proteomics of Brucella [ 43 , 44 ]. None of the differentiating genes for B. melitensis that we identified have yet been detected in the proteome in vitro ; however, the above proteomics study resulted in annotation of only 6% of the predicted genes in B. melitensis .…”

Pan-Proteomic Analysis and Elucidation of Protein Abundance among the Closely Related Brucella Species, Brucella abortus and Brucella melitensis

“…Application of LC-MS has enhanced the protein coverage as demonstrated in the case of reference strain B. abortus 2308 to create a dataset of 621 proteins among which 300 were not reported earlier and five were attributed to pseudogenes [29]. LC-MS-based quantitative proteomic comparison of the outer membrane fraction of virulent and avirulent strains of B. abortus results in the fact that Brucella virulence is based on extensive cell envelope-based modifications [26,30,55]. Therefore, the present study involving LC-MS-based quantitative proteomic analysis of whole-cell protein extracts was initiated to identify protein expression level differences between these two closely related bacterial species.…”

“…Although it is broadly accepted in the field that the Type IV secretion system (T4SS) is in some way tied to virulence in Brucella species, Brucella generally lacks classical virulence factors and in order to explain its virulence and host specificity, a better understanding at the proteome and metabolome level is needed. Proteomic analyses of various strains of B. abortus and B. melitensis have been reported [ 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 ], suffering from limitations in terms of technology and database coverage. In the present study, the label-free quantitative proteomic analysis includes the reference strains as well as strains isolated from infected animals analyzed in an earlier study [ 23 ].…”