St. Jude Children’s Research Hospital scientists have discovered an enzyme that regulates production of the toxins that contribute to potentially life-threatening Staphylococcus aureus infections. The study appeared online on July 7, 2014 in PNAS. Researchers also showed that the same enzyme allows Staphylococcus aureus to use fatty acids acquired from the infected individual to make the membrane that bacteria need to grow and flourish. The results provide a promising focus for efforts to develop a much-needed new class of antibiotics to combat staph and other Gram-positive infections. Staphylococcus aureus is the most common cause of staph infections, including methicillin-resistant Staphylococcus aureus (MRSA), the drug-resistant infection that is a growing problem in hospitals. “Staphylococcus aureus is a clear and present danger to patients worldwide,” said corresponding author Charles Rock, Ph.D., a member of the St. Jude Department of Infectious Diseases. “We set out to answer a long-standing question about bacterial membrane biochemistry and discovered a master regulator of the virulence factors that make staph infections so destructive and dangerous. The pathway we identified offers an exciting new target for antibiotic drug development.” Virulence factors include dozens of proteins that bacteria make and secrete. The factors cause many symptoms and infection-related problems, including destruction of cells and tissue, and evasion of the immune system. The enzyme Dr. Rock and his colleagues discovered is fatty acid kinase (FAK). Researchers showed that FAK is formed by the proteins FakA and FakB1 or FakB2. Scientists demonstrated how FakA and FakB work together to replace fatty acids in the bacterial membrane with fatty acids from the person infected.Login Or Register To Read Full Story