Highly epidemic strains of methicillin-resistant Staphylococcus aureus (MRSA) do not differ from other MRSA or methicillin-sensitive strains in capsule formation, Protein A content or adherence to HEp-2 cells

During the 1990s, two strains of epidemic methicillin-resistant Staphylococcus aureus, designated ‘phage types EMRSA-15 and EMRSA-16, have emerged as significant hospital pathogens. They have resisted standard methods of control and spread widely amongst in the UK, often becoming endemic, while the incidence of other epidemic types of MRSA has either declined or not changed. This suggests that EMRSA-15 and EMRSA-16 possess special properties that favour their dissemination and survival. In order to investigate this hypothesis, a study was undertaken that examined methicillin-sensitive and methicillinresistant strains of Staphylococcus aureus, including EMRSA types 1, 2, 3, 15 and 16, for capsule formation,
the amount of bound protein A produced, and quantitative adherence to the human continuous epithelial cell line HEp-2. Although all these properties varied amongst the strains examined, there was no relationship between any of them and methicillin resistance or epidemic type, and, incidentally, no relationship between
cell-wall bound protein A content and adherence.

Citation:
Aathithan S, Dybowski R, French GL. (2001) "Highly epidemic strains of methicillin-resistant Staphylococcus aureus (MRSA) do not differ from other MRSA or methicillin-sensitive strains in capsule formation, Protein A content or adherence to HEp-2 cells". European Journal of Clinical Microbiology and Infections Diseases, 20 (1) 27-32.