With a view to exploring the role of alpha toxin in staphylococcal infections, attempts were made to purify the toxin and to clarify pathogenic effects of thus purified preparation.
Using supernatant fluid of a brain heart infusion broth culture of
Staphylococcvs aureus, strain Wood 46 as starting material, an alpha toxin preparation was obtained by concentration and purification through chromatographic column in various combination including DEAE-Sephadex column; and the preparation thus obtained has proven to be highly homogenous, both physically and immunologically.
The hemolytic activity of this toxin was 73, 142.8MHD/Nmg, purification rate was 497.9, and recovery was 1.5 per cent. And S
20-w was about 3.2 S.
Chemical examination revealed an alpha toxin consisting of a total of 13 amino acid groups, i.e., asparagine, serine, threonine, glutamine, proline, glycine, alanine, valine, isoleucine, leucine, phenylalanine, lysine, and arginine but devoid of saccharide, hexosamine, phosphorus, and lipid.
Its hemolytic as well as leucocidin effects were found to be remarkably profound with the blood cells of rabbits, while it affected the cells of mice and man only to a small extent, suggesting its marked species-specificity in these respects. The results of further experiments regarding its lethal effects in mice and dermonecrotic effects in rabbits along with its said behavior as hemolysin all provided evidence in support of the unitarian theory.
The alpha toxin preparation produced a characteristic cytopathogenic effect only in rabbit kidney cell cultures in as low a dose as 2 MHD, while it proved to be practically lacking in cytopathogenic effects on cultures of monkey kidney, Hela, L, and FL cell lines.
Inoculations with pathogenic strains of the Staphylococci apparently resulted in localised abscesses in rabbits, whereas mice were found undoutedly to be resistant.
These experimental findings in all appear to suggest that the biologic activity of the toxin is of cardinal importance in the pathogenesis of staphylococcal infections in rabbits alone, but is extremely minor importance in man.
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