Project description:Streptococcus equi subspecies equi (S. equi) is a major pathogen which cause strangles, a highly contagious respiratory infection, in horses and other equines. In this study, we purified the extracellular vesicles (EVs) of S. equi ATCC 39506 and evaluated them as vaccine candidates against S. equi infections in mice. Through immunization in an animal model and immunoprecipitation-mass spectrometry, we evaluated EV as vaccine candidates against S. equi infections and identified novel immunogenic proteins.
Project description:Streptococcus equi subspecies equi (S. equi) is a major pathogen which cause strangles, a highly contagious respiratory infection, in horses and other equines.In this study, we discovered potential vaccine candidates using comprehensive proteomics and reverse vaccinology. As the initial step, we divided proteome of S. equi ATCC 39506 into whole cell lysate, secretory proteome, membrane proteome and extracellular vesicle and then, comparative proteomic analysis was performed to characterize the functional features of the proteome. Especially, extracellular vesicle of S. equi was evaluated at the first time. Total 114 potential vaccine candidates (PVCs) were selected using reverse vaccinology and knowledge based annotations. Comprehensive proteomic analysis confirmed that 60 PVCs were identified in S. equi ATCC 39506. Particularly, 32 PVCs were enriched in the EV proteome, suggesting that this cellular fraction may serve as vaccine.
Project description:Streptococcus equi subspecies equi, strain 1691 grown on COBA streptococcal selective agar shows classical mucoid colony morphology in addition to a reduced capsule phenotype. This project aimed to identify changes in the transcriptional profile between the two morphologies.
Project description:Streptococcus equi subsp. equi (SEE) is a host-restricted bacterium that causes the common infectious upper respiratory disease known as strangles in horses. Perpetuation of SEE infection appears attributable to inapparent carrier horses because it does not persist long-term in the environment, infect other host mammals or vectors, and result in short-lived immunity. Whether pathogen factors enable SEE to remain in horses without causing clinical signs remains poorly understood. Thus, our objective was to use next-generation sequencing technologies to characterize the transcriptome of isolates of SEE from horses with acute clinical strangles and inapparent carrier horses to assess pathogen-associated changes that might reflect adaptions of SEE to the host contributing to inapparent carriage. RNA sequencing of SEE isolates from Pennsylvania demonstrated no genes that were differentially expressed between acute clinical and inapparent carrier isolates of SEE.
Project description:CsrRS is a two component regulator which is known to regulate 10-18 % of the genome of the closely related Streptococcus pyogenes. We aimed to look for transcriptional differences between pairs of naturally occurring Streptococcus equi strains where one possessed a SNP in csrRS whereas the other did not. Such SNPs have not been identified in isolates from acute disease but have been identified in persistent isolates.
