Abstract
Background: Staphylococcus aureus is one of the most important pathogens acquired from the hospital and community. Increasing the resistance of S. aureus to antibiotics is a major health concentration, and thus the study of antibiotic resistance in S. aureus is very important. The aim of this study is to determine the typing of methicillin-resistant S. aureus (MRSA) in the region of the ccrB gene by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).
Methods: One hundred and six S. aureus were isolated from urine, blood, sputum, wound, and the trachea of patients hospitalized in Tehran during (March-April) 2016. Antibiotic susceptibility test was done by the disk diffusion method according to the Clinical and Laboratory Standards Institute (CLSI). In addition, molecular typing for staphylococcal cassette chromosome mec (Sccmec) type I-V was performed in MRSA isolates, followed by conducting PCR-RFLP by restriction enzymes BsmI and HinfI in the ccrB gene area.
Results: PCR and typing showed that type II SCCmec was 40% (n=20), followed by types III (28, 56%), IVc (12, 24%), I (11, 22%), V (9, 18%) IVa (7, 14%), and IVb (5, 10%). However, SCCmec type IVd was not observed in the isolates. Finally, after the amplification of ccrB gene and RFLP, all isolates the same as the typing method represented types I, II, III, IVa, IVb, and IVc while no type V was detected by this method.
Conclusions: The results of this study demonstrated that SCCmec (type I-IV) can be detected by PCR-RFLP in the ccrB gene, but this method identified no type V SCCmec in MRSA