General Information: Streptococcus equi equi is an obligate parasitic bacterium and is the causative agent of a serious upper respiratory tract disease within members of the family Equidae (horses), called strangles. Strangles is a highly contagious disease of the nasopharynx and lymph nodes. The genome sequence of this organism will provide information into the production and regulation of virulence factors involved in this disease. Pathogenic in horses, goats and sheep. Streptococci are Gram-positive, nonmotile, nonsporeforming, catalase-negative cocci that occur in pairs or chains. Members of this genus vary widely in pathogenic potential. Most streptococci are facultative anaerobes, and some are obligate anaerobes.