Burkholderia pseudomallei is the causative agent of Melioidosis, an endemic disease in South East Asia, and is classified as a category B biological agent. Currently, there is no licensed vaccine for this disease; the mortality rate is high due to the incorrect diagnosis and the pathogen insusceptibility to general antibiotics. A mass spectrometry based proteomic approach has been applied in order to identify the proteins that are responsible for pathogenicity.

Methods were developed for the proteomic analysis of Burkholderia species using B. vietnamiensis G4, an opportunistic pathogen as the model organism. Both gel-based (LC-MS/MS) and gel-free MudPIT (LC/LC-MS/MS) approaches have been applied for the analysis of the proteins extracted from four different cellular fractions of these bacteria. More than 1200 proteins were identified from these analyses, including many proteins previously identified as virulence factors of these bacteria. Similar methodologies were applied to build a proteome map of non-pathogenic B. thailandensis E264 to use as a reference for the pathogenic studies. Additionally, proteomes of two B. thailandensis strains isolated from two geographical locations were compared to investigate the differences in protein expression of these organisms.

Proteins identified from pathogenic B. pseudomallei were compared with the non-pathogenic B. thailandensis and opportunistic pathogen B. vietnamiensis proteins. Many species specific proteins were identified from this proteomic analyses; those proteins can be used as antigen targets to selectively identify these pathogenic bacteria in a complex biological matrix using affinity capture methods.

Ticks are vectors that can transmit disease causing pathogens one host to another. Knowing the pathogen reservoir is important in order to control disease spread in the environment. Application of mass spectrometric methods to identify the host blood components from tick vectors was investigated using tick nymphs which feed only once in their life cycle. Using mass spectrometry based proteomics; host specific proteins like hemoglobin and immunoglobulin were identified from a single tick nymph analysis. Additional studies have examined the fatty acid profiles of rabbit and sheep blood fed tick nymphs using SPALDI mass spectrometry. Different fatty acid profiles were obtained for these tick nymphs, but further investigations are required to validate these findings.