Comparative Genomics of S. aureus

S. aureus is the most pathogenic species of the genus Staphylococcus, being one of the most successful pathogens in hospitals. The types of infections caused by S. aureus range from mild superficial infections of the skin like furuncle, wound infections, and carbuncle to life-threatening infections including sepsis, endocarditis, and pneumonia [4]. Moreover, the organism is one of the leading causes of foodborne diseases [5]. S. aureus produces an extraordinary number of virulence traits such as superantigen toxins, hemolysins, adhesins, and degradative enzymes; most of them play a significant role in virulence [6]. Importantly, S. aureus easily acquires antibiotic resistance determinants which favor survival in the highly competitive environment of hospitals. Since the 1980s MRSA has emerged as a major nosocomial pathogen. In several countries including the United States, Japan, and the United Kingdom, MRSA is the causative agent of more than 50% of nosocomial infections in intensive care units [7, 8]. For these cases, the glyco-peptide antibiotic vancomycin remains the drug of last resort. In 1997, however, the first case of vancomycin-intermediate S. aureus (VISA) appeared, and in 2002 the first case of a high-level vancomycin-resistant S. aureus strain expressing the vanA gene cluster of enterococci was isolated [9-12]. The high-level vancomycin resistance vanA-carrying transposon Tnl546 has been horizontally transferred from E.faecalis to S. aureus in the hospital setting [13].

0 0

Post a comment