DESTRUCTION OF LACTOBACILLI BY STAPHYLOCOCCUS AUREUS BACTERIOCIN-LIKE INHIBITORY SUBSTANCES

Aim. Determination of morpho-physiologi -
cal changes in cells of a lactobacillus industry
strain suppressed by antagonistically active
clinical cultures of Staphylococcus aureus.
Materials and methods. 5 clinical strains of
Staphylococcus aureus detected among 42 strains
isolated previously in atopic dermatitis were
used. Bacteria of the industry strain Lactobacillus
plantarum 8PA-3 that synthesize bacteriocinlike
inhibitory substances (BLIS) were used as
target-cells. Suppression of growth of lactobacilli
cells by staphylococci was performed on
modified agar nutrient medium MRS by delayed
antagonism method. Ultrastructure changes in
lactobacilli cells exposed to staphylococci BLIS
were studied by various methods of transmission
electron microscopy. Results. Destructive
changes (exfoliation of small layered fragments
of peptidoglycan layers) were detected in the
cell walls of lactobacilli suppressed by staphylococci
BLIS, and rearrangement of ultrathin
structure of their cytoplasm with the destruction
of protein-ribosomal complex was noticed.
Conclusion. Clinical S. aureus strains that produce
BLIS, suppress antagonistic activity of
lactobacilli were revealed, and morpho-physiological
changes in lactobacilli target-cells
damaged by BLIS were detected. Local damage
of cell components manifested by the destruction
of cytoplasm and formation of «ell shadows
»

Staphylococcus aureus, Lactobacillus plantarum 8PA-3, antagonism, lactobacilli target-cells, ultrastructure changes, Staphylococcus aureus, Lactobacillus plantarum 8PA-3