The characterization of industrial yeast strains by examining their metabolic footprints (exometabolomes) was investigated and compared to genome-based discriminatory methods. A group of nine industrial brewing yeasts was studied by comparing their metabolic footprints, genetic fingerprints and comparative genomic hybridization profiles. Metabolic footprinting was carried out by both direct injection mass spectrometry (DIMS) and gas chromatography time-of-flight mass spectrometry (GC-TOF-MS), with data analysed by principal components analysis (PCA) and canonical variates analysis (CVA). The genomic profiles of the nine yeasts were compared by PCR-restriction fragment length polymorphism (PCR-RFLP) analysis, genetic fingerprinting using amplified fragment length polymorphism (AFLP) analysis and microarray comparative genome hybridizations (CGH). Metabolomic and genomic analysis comparison of the nine brewing yeasts identified metabolomics as a powerful tool in separating genotypically and phenotypically similar strains. For some strains discrimination not achieved genomically was observed metabolomically.

Mucosal immunization is advantageous over other routes of antigen delivery because it can induce both mucosal and systemic immune responses. Our goal was to develop a mucosal delivery vehicle based on bacteria generally regarded as safe, such as Lactobacillus spp. In this study, we used the Lyme disease mouse model as a proof of concept. We demonstrate that an oral vaccine based on live recombinant Lactobacillus plantarum protects mice from tick-transmitted Borrelia burgdorferi infection. Our method of expressing vaccine antigens in L. plantarum induces both systemic and mucosal immunity after oral administration. This platform technology can be applied to design oral vaccine delivery vehicles against several microbial pathogens.Lactic acid bacteria are naturally associated with mucosal surfaces, particularly the gastrointestinal tract, and are also indigenous to food-related habitats, including plants, wine, milk, and meat. These gram-positive bacteria include both important pathogens, e.g., several Streptococcus species, and extremely valuable nonpathogenic species that have been used since ancient times for food and feed fermentation (11,37,58). The host is highly adapted to the presence of commensal intestinal bacteria (36). There is evidence that some strains of lactic acid bacteria have a favorable influence on physiologic and pathological processes of the host due to their specific health-promoting probiotic characteristics that relate to modulation of the immune system (15,36,41). Some strains of lactic acid bacteria polarize the naïve immune system by skewing it toward Th1 responses (41, 56).There have been a number of reports of oral vaccine candidates established from genetically modified pathogenic bacteria, such as Salmonella and Listeria species (1, 2, 30, 45, 52), or commensal bacteria, such as Lactococcus lactis and Lactobacillus species (27,31,32,60). The latter are food-grade bacteria that have GRAS status (generally regarded as safe). While both pathogenic and commensal bacteria have advantages and disadvantages as mucosal delivery vehicles, lactic acid bacteria are preferable in terms of safety and a lower risk of side effects (27,47). Presentation of antigens on the surface of lactobacilli is attractive for vaccine design, especially because the peptidoglycan layer of some strains appears to exhibit natural immuno-adjuvanticity (33,35,44,46). Thus, these species are excellent candidates for the development of safe mucosal delivery vehicles of prophylactic and therapeutic molecules. Of the Lactobacillus strains previously used for vaccine delivery, we chose L. plantarum because there is evidence that this strain is a better agent for vaccination with tetanus toxin fragment C (TTFC) than L. casei or L. lactis (22,53).Lyme disease is the most prevalent vector-borne infectious disease in the United States. A vaccine administered via needle inoculation and based on outer surface protein A (OspA) has proved effective in preventing Borrelia burgdorferi infection in animals and humans (7,10,(16)(17)...

Early diagnosis of Lyme disease (LD) is critical to successful treatment. However, current serodiagnostic tests do not reliably detect antibodies during early infection. OspC induces a potent early immune response and is also one of the most diverse proteins in the Borrelia proteome. Yet, at least 70% of the amino acid sequence is conserved among all 21 known OspC types. We performed a series of comprehensive seroprofiling studies to select the OspC types that have the most crossreactive immunodominant epitopes. We found that proteins belonging to seven OspC types detect antibodies from all three infected host species regardless of the OspC genotype of the infecting strain. Although no one OspC type identifies all seropositive human samples, combinations of as few as two OspC proteins identified all patients that had anti-OspC antibodies.