Antibiotic Resistance Within Staphylococcus Aureus
Staphylococcus aureus is a growing issue both within hospitals and communities because of its ability to adjust to different environments. Over the years, S. aureus has become resistant to many different antibiotics including penicillin and methicillin. Today, Staphylococcus aureus remains a growing pandemic because of its increasing antibiotic resistance through different mechanisms including horizontal gene transfer and altering of antibiotics.
Introduction
Staphylococcus aureus is a gram positive bacteria that belongs to the micrococcaceae family and appears in the form of cocci clusters. It differs from other staphylococcus because it appears with gold pigmentation. The bacteria also tests positive for coagulase, mannitol-fermentation, and deoxyribonuclease. Staphylococcus aureus has a thick cell wall made up of peptidoglycan and in this case are 50 percent by weight. The peptidoglycan are made up of both N-acetylglucosamine and N-acetylmuramic acid, which are linked with tetrapeptide chains, found only in S. aureus. It contains prophages, plasmids, and transposons all within a 2800 bp circular chromosome [1]. This is where mechanisms of antibiotic resistance are found. The bacteria was first discovered by Alexander Ogston in 1880 when he became interested in the high post surgery mortality rates, and was later named by Friedrich Julius Rosenbach. More commonly referred to as a “staph infection” or “staph bacteria”, S. aureus is reportedly found in 30% of the population who are asymptomatic nasal carriers, while another large portion carry the bacteria on their skin.[2] S. aureus is transferred through skin to skin contact and more commonly affects persons previously diseased or with weaker immune systems. The most common transfer happens from a health worker who has been in contact with an active strain of it. Other transfers occur from environmental sources or from other carriers of the bacteria. Possible outcomes from staph infections include many hospital originated issues including pneumonia and bloodstream and wound infections. When S. aureus was first identified, and before antibiotics were developed, the bacteria had a mortality rate of 80%. Today, with antibiotic treatment, the mortality rates around the world range from 20-40% [3].
Penicillin Resistance: History and Mechanisms
Include some current research in each topic, with at least one figure showing data.
Methicillin: History and Resistance
Include some current research in each topic, with at least one figure showing data.
Further Reading
[Sample link] Ebola Hemorrhagic Fever—Centers for Disease Control and Prevention, Special Pathogens Branch
References
Edited by (your name here), a student of Nora Sullivan in BIOL168L (Microbiology) in The Keck Science Department of the Claremont Colleges Spring 2014.
