[Frontiers in Bioscience S4, 900-915, January 1, 2012]

Chromosomal mutations involved in antibiotic resistance in Staphylococcus aureus

Bjorn A. Espedido1, Iain B. Gosbell1,2

1Antibiotic Resistance and Mobile Elements Group (ARMEG), Microbiology and Infectious Diseases Unit, School of Medicine, University of Western Sydney, New South Wales, Australia, 2Department of Microbiology and Infectious Diseases, Sydney South-West Pathology Service Liverpool, Sydney, New South Wales, Australia

TABLE OF CONTENTS

1. Abstract
2. Introduction
3. Resistance to cell wall active agents
3.1. Beta-lactams
3.2. Glycopeptides
3.2.1. Vancomycin
3.2.2. Teicoplanin
3.2.3. Lipopeptides
4. Resistance to nucleic acid synthesis inhibitors
4.1. Quinolones
4.2. Coumarins
4.3. Folate synthesis inhibitors
4.4. Rifamycins
5. Resistance to protein synthesis inhibitors
5.1. Macrolides, lincosamides & streptogrammins
5.2. Oxazolidinones
5.3. Aminoglycosides
5.4. Tetracycline antibiotics
5.5. Pseudomonic acid
5.6. Steroids
6. Small colony variants
7. Conclusion
8. Acknowledgements
9. References

1. ABSTRACT

Staphylococcus aureus is an important pathogen involved in infections in both the community and hospital setting. Strains that are resistant to multiple classes of antibiotics, particularly methicillin-resistant strains (MRSA), are prevalent in nosocomial infections and are associated with high morbidity and mortality rates. Such antibiotic-resistant strains limit the therapeutic options and place a burden on the health care system. In the hospital setting, horizontal gene transfer plays an important role in disseminating antibiotic resistant determinants among S. aureus. However, resistance to all known classes of antibiotics have been attributed to genes found within the S. aureus chromosome or to due to mutation as a result of selection pressure. Spontaneous mutations, in particular, are pivotal in the emergence of novel resistances. Consequently, newer drugs with better activity and/or antibacterial agents with novel targets need to be developed to combat and control the further spread of antibiotic resistance.