Project description:Comparison of Campylobacter proteome in MH media with and without deoxycholic acid, in presence of FBS or after being exposed to INT 407 and Caco2 intestinal epithelial cells.
Project description:Many pathogenic bacteria of the family Enterobacteriaceae use type III secretion systems to inject virulence proteins, termed "effectors," into the host cell cytosol. Although host-cellular activities of several effectors have been demonstrated, the function and host-targeted pathways of most of the effectors identified to date are largely undetermined. To gain insight into host proteins targeted by bacterial effectors, we performed coaffinity purification of host proteins from cell lysates using recombinant effectors from the Enterobacteriaceae intracellular pathogens Salmonella enterica serovar Typhimurium and Citrobacter rodentium. We identified 54 high-confidence host interactors for the Salmonella effectors GogA, GtgA, GtgE, SpvC, SrfH, SseL, SspH1, and SssB collectively and 21 interactors for the Citrobacter effectors EspT, NleA, NleG1, and NleK. We biochemically validated the interaction between the SrfH Salmonella protein and the extracellular signal-regulated kinase 2 (ERK2) host protein kinase, which revealed a role for this effector in regulating phosphorylation levels of this enzyme, which plays a central role in signal transduction. IMPORTANCE During infection, pathogenic bacteria face an adverse environment of factors driven by both cellular and humoral defense mechanisms. To help evade the immune response and ultimately proliferate inside the host, many bacteria evolved specialized secretion systems to deliver effector proteins directly into host cells. Translocated effector proteins function to subvert host defense mechanisms. Numerous pathogenic bacteria use a specialized secretion system called type III secretion to deliver effectors into the host cell cytosol. Here, we identified 75 new host targets of Salmonella and Citrobacter effectors, which will help elucidate their mechanisms of action.
Project description:Utilized sensitive, high throughput multiplexed ion mobility-mass spectrometry (IM-MS) to characterize the serum proteome of tuberculosis patients prior to and at 8 weeks of antibiotic treatment. Goal is to identify a serum protein signature indicative of treatment effect.
Project description:Quantitative proteome analysis of progressive phycobilisome mutant variants CB, CK, and PAL to understand systematic alterations in protein expression profiles.
Project description:We have developed a quantitative chemical probe approach for live cell labeling of proteins that are sensitive to redox modifications. We utilize this in vivo strategy coupled to mass spectrometry-based proteomics to identify 176 proteins undergoing ~5-10 fold dynamic redox change in response to nutrient limitation and subsequent replenishment in the photoautotrophic cyanobacterium, Synechococcus sp. PCC 7002. This method enables the identification of redox changes in as little as 30 seconds after nutrient perturbation, and oscillations in reduction and oxidation for 60 minutes following the perturbation. The redox changes were validated by demonstrating that protein abundances did not change per global proteomic analyses. Peptides identified by MS for global and probe-labeled samples were required to be at least six amino acids in length having a mass spectra generating function score of <=1E-10, which corresponds to an FDR of <1%. Additionally, only peptides unique in identifying a single protein were utilized to estimate protein abundances, and proteins represented by <2 unique peptides were removed. This resulted in the identification of 176 redox probe labeled protein identifications, and 808 protein identifications in the global data.
Project description:Data includes proteomics analysis of P450-ABP (2EN, ATW8, ATW12), FP-2, and ATP-ABP labeled mouse lung lysate S9. Lungs from the following developmental stages were used in the study: gestational day 17, post natal days 0, 21, and 42. Also included are global analyses of the same mice lungs.
Project description:We sampled global bottom up proteomics data from 48 diverse bacteria and searched for sites of lysine acetylation. Bacteria came from 6 phyla: proteobacteria, cyanobacteria, firmicutes, bacteroidetes, actinobacteria, and fibrobacteres.
Project description:Elucidating the metabolome of the filamentous fungi Neurospora crassa to better understand the link between the circadian clock and metabolism; specifically the role that the clock plays in regulating cellulase production.