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Updated: Jul 19, 2026

Genotyping of Staphylococcus aureus by Ribosomal Spacer PCR (RS-PCR)
Published on: November 4, 2016
[Characteristics of clumping factor- and protein A-negative methicillin-resistant Staphylococcus aureus identified in
K Garbacz1, L Piechowicz, J Galiński
1Institut de Microbiologie Médicale de l'Académie de Médecine de Gdańsk, 38, ul. Do Studzienki, 80-227 Gdańsk, Pologne. kasgab@amg.gda.pl
Aim:
The aim of this study was to investigate the phenotypic and genotypic properties of clumping factor- and protein A- negative MRSA.
Methods:
Two hundred ninety-four strains were studied. The production of protein A was determined by immunoblotting, clumping factor (CF) and coagulase by conventional tests with rabbit plasma. The presence of nuc gene and mecA gene was identified by PCR. The presence of clfA and spa genes was determined for CF- and protein A-negative strains and then phage typing was performed using two sets of phages and gene typing by RFLP of the spa gene.
Results:
Sixteen (5.4%) CF- and protein A-negative MRSA were isolated. All of them produced coagulase and thermostable nuclease (except for one). nuc, mecA, spa and clfA genes were observed in all strains. The same RLFP pattern, but with different phage types and resistance profiles to antibiotics, was observed in all strains.
Conclusions:
CF- and protein A-negative methicillin resistant S. aureus isolated in Poland do not come from a single clone and the absence of CF and protein A is not caused by the deletion of clfA and spa genes.
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