Expression of SElX was detected in 13 of 15 isolates including 5 of 5 human isolates from sepsis, scalded skin syndrome and infective endocarditis patients, 4 of 4 bovine mastitis isolates, 3 of 4 ovine mastitis isolates, and a single caprine mastitis isolate. The gene discussed is MSRB1; the disease is infective endocarditis.