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Methicillin Research Papers

Decent Essays
Streptococcus aureus is a universally known gram-positive bacterium and is most commonly found in infections. It is also known to have an ability to evolve and adapt to antibiotics such as penicillin and methicillin. S. aureus was regularly treated with penicillin up until the point it obtained a resistance to penicillin around 1948. This occurrence caused the switch from penicillin to methicillin to treat infections with S. aureus. However, over time Streptococcus aureus gained and developed several strains that are resistant to methicillin around 1961. These strains are known as MRSAs, which is short for methicillin resistant Streptococcus aureus. (Robinson 2003) Although not everything about the methicillin resistance in S. aureus is known,…show more content…
aureus originated from. It was theorized that the evolution of methicillin-resistant S. aureus must have begun with the gain of the mecA determinant (which is the gene in bacteria that allows it to be resistant to antibiotics) from an unknown heterologous source before the first appearance in the U.K. and Denmark of MRSA isolates in the 1960s. Genetic backgrounds and phenotypes of a group of methicillin-susceptible S. aureus isolates have been compared to the MRSA strains isolated in Denmark and the U.K. during the same time. The genetic profiles of contemporary epidemic clones of MRSA were compared as well. The samples of these experiments were taken from the first MRSA isolated in a British hospital in 1961 and the first Danish blood isolates of MRSA recovered in 1963. It was first hypothesized that early MRSA isolates could represent the progeny of MSSA which was the original recipient of the heterologous mec element. If this were indeed true, then it could be expected to identify the postulated recipient among MSSA strains originating in the same geographic area and time. The results of the experiments confirmed the previous hypothesis made by displaying distinct similarities between MRSA strains and most of the MSSA isolated in Denmark and the U.K. during the same time period. The earliest MSSA examined shared a common phage group and
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