Evolution and Single-Nucleotide Polymorphisms in Methicillin- Resistant Staphylococcus aureus Strains with Reduced Susceptibility to Vancomycin and Daptomycin, Based on Determination of the

We obtained a series of methicillin-resistant Staphylococcus aureus isolates, including both daptomycin-susceptible strain TD1 and daptomycin-resistant strain TD4, from a patient. We determined the complete genome sequences of TD1 and TD4 using next-generation sequencing, and only four single-nucleotide polymorphisms (SNPs) were identified, one each in capB (E58K), rpoB (H481Y), lytN (I16V), andmprF (V351E). We determined that these four SNPs were sufficient to cause the strains to de-velop daptomycin, vancomycin, and rifampin resistance. Methicillin-resistant Staphylococcus aureus (MRSA) is one ofthe most significant human bacterial pathogens, causing a wide range of clinical diseases among hospital patients and in the community. The use of anti-MRSA agents, such as vancomyci