Bactericidal and bacteriolytic activity of Listeria
- B. SKALKA
- Acta vet. Bmo,
Skalka B.: Antibacterial Effects of Staphylococcus hyicus and Staphylococcus chromogenes. Acta vet. Bmo, 62, 1993: 39-47. Antibacterial effects of Staphylococcus hyicus (40 strains) and Staphylococcus chromo genes (20 strains) were tested on living and heat-devitalized cells of micrococcal, staphylococcal, streptococcal and corynebacterial indicator strains. All S. hyicus and S. chromo genes strains inhibited the growth of Micrococcus sedentarius and lysed devitalized cells of Micrococcus lylae but did not affect dead cells of M. sedentarius and only few of them inhibited the growth of M. lylae. Only a small number of S. hyicus strains produced intense effects on living indicators and had only very weak effects on their dead cells. The activity of some S. chromogenes strains, observed invariably on living indicators, did not reach the intensity recorded for active S. hyicus strains. Most S. hyicus and S. chromo genes strains were inactive towards the indicators. It is concluded that the antibacterial activity observed in the study should be ascribed to the characteristics of the individual strains and not to the general characteristics of S. hyicus and S. chromo genes species. Staphylococcus hyicus, Staphylococcus chromo genes, antibacterial effects, staphylococcal, micrococcal, streptococcal and corynebacterial indicator strains Staphylococcal exosubstances showing antibacterial activity are represented both by lytic enzymes, lysozyme (Welsch 1959) affecting somemicrococci,lysostaphin (Schindler and Schuhardt 1964) affecting staphylococci, and by substances having bactericidal or bacteriostatic effects, staphylococcins (Fredericq 1946), bacteriocin-like substances (Ivanovics 1962), micrococcins (Su 1948) and antibiotics of low molecular weight (Halbert et a1. 1953). Recently added to the afore-mentioned substances have been exosubstances of the species Staphylococcus hyicus nad Staphylococcus chromo genes. The first report of the antibacterial activity of S. hyicus and S. chromo genes (Balusek and Hajek 1985) described bactericidal and bacteriolytic activity observed in some strains of these two species. The lytic effects in particular then stimulated the interest of further investigators. Miillerand Blobel (1987) reported that a S. hyicus strain produced a bacteriolytic enzyme whose highly purified fractions, LE IlIa and LE IIlb, exerted intense effects on devitalized cells of some streptococci, staphylococci and micrococci. Subsequent studies not only confirm'rd the lytic effects of LE IlIb but also recommended the utilization of this lytic enzyme for extraction of both group and type specific streptococcal antigens (Frede et a1. 1989; Lammler and Wibawan 1990). It was suggested that the production of the lytic enzyme should be regarded as a constant trait of S. hyicus suitable for routine identification of this species (Lammler 1989, 1991a). The production was also described in S. chromogenes and its antigenic identity with the lytic enzyme of S. hyicus was demonstrated (Lammler 1991b). The present study was designed to test the antibacterial effects of S. hyicus and S. chrom()genes on micrococcal, staphylococcal, streptococcal and corynebacterial species with reference to possible practical utilization of these effects. Materials and Methods Culture Media , Brain'Heart Infusion Agar CM 375 (Oxoid Ltd.) and Blood Agar Base No.4 (Imuna) were used. '