[Selected properties of Staphylococcus aureus strains using phenotype to show a lack of coagulase synthesis]

Eighteen of S. aureus strains isolated from clinical specimens and showing negative reaction for coagulase in conventional tube test were characterized by using five different methods: ID32 Staph, API Staph, Gpl-15, STAPH-ZYM (Rosco) and classical tube methods. The membership of all examined strains to S. aureus subsp. aureus was confirmed. None of the strains produced detectable amounts of coagulase but all of them produced protein A and clumping factor. All of them were typable with phages of the III lytic group and 11 of them possessed phage pattern characteristic of the 83A complex. All the investigated hospital strains were resistant to methicillin. Five showed homogenous and 13 heterogenous type of methicillin resistance. Moreover, all of them were resistant to tetracycline, gentamicin, tobramycin and kanamycin and to MLS group of antibiotics.