Abstract
On the addition of small concentrations of deoxyribonuclease, produced by Staphylococcus aureus, to Toluidine Blue DNA agar, a medium is produced on which antibodies against S. aureus deoxyribonuclease may be detected. When samples of milk, or blood serum, containing antibodies against S. aureus are applied into wells in the agar, the deoxyribonuclease activity is inhibited by the antibodies diffusing into the agar. As a result of this inhibition, blue zones are produced around the wells in the otherwise bluish-red agar. The diameters of the zones correspond to the concentrations of antibodies, and the method may consequently be used for qualitative and quantitative examinations of antibodies against S. aureus deoxyribonuclease in milk and serum. The procedure and certain limitations of the method are described.
Keywords: deoxyribonuclease, Staphylococcus aureus, antibodies.
Sammendrag
Et medium for påvisning av antistoff mot deoxyribonuklease produsert av Staphylococcus aureus kan lages ved å tilsette lave konsentrasjoner av stafylokokk-deoxyribonuklease til toluidinblått-DNA-agar. Når prøver av melk eller blodserum dryppes ut i brønner i agaren, vil antistoffene som diffunderer ut i mediet, hemme virkningen av deoxyribonuklease. Som en følge af dette vil det utvikles blå soner rundt brønnene i det ellers blå-røde mediet. Diameteren på sonene vil avhenge av konsentrasjonen av antistoff og metoden kan derfor benyttes ved kvalitative og kvantitative undersøkelser av antistoff mot stafylokokk-deoxyribonuklease i melk og serum. Metoden og enkelte begrensninger ved den er beskrevet.
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References
- Erickson A, Deibel R H. Turbidimetric assay of staphylococcal nuclease. Appl. Microbiol. 1973;25:337–341. doi: 10.1128/AM.25.3.337-341.1973. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fossum K. Proteolytic enzymes and biological inhibitors. I. Comparison between the Kunitz method and the agar gel casein precipitating reaction for determination of the activity of some commercial proteolytic enzymes and inhibitors. Acta path, microbiol. scand. Section B. 1970;78:350–362. [PubMed] [Google Scholar]
- Gudding R. Heat stable nuclease in mastitic milk. Acta vet. scand. 1976;17:501–502. doi: 10.1186/BF03547906. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gudding R. DNases in milk and blood sera from different species. 1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lachica JR V F, Genigeorgis C, Hoeprich P D. Metachromatic agar-diffusion methods for detecting staphylococcal nuclease activity. Appl. Microbiol. 1971;21:585–587. doi: 10.1128/AM.21.4.585-587.1971. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sachs D H, Schechter A N, Eastlake A, Anfinsen C B. Antibodies to a distinct antigenic determinant of staphylococcal nuclease. J. Immunol. 1972;109:1300–1310. [PubMed] [Google Scholar]
- Sandvik O. Studies on casein precipitating enzymes of aerobic and facultatively anaerobic bacteria. Oslo: Veterinary College of Norway; 1962. p. 116. [Google Scholar]
- Sandvik O. The occurrence of antibodies against staphylococcal deoxyribonucleases in bovine milk. Acta vet. scand. 1974;15:631–635. doi: 10.1186/BF03547232. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sandvik O. The occurrence of antibodies against staphylococcal deoxyribonucleases in bovine milk. Acta vet. scand. 1975;16:140–142. doi: 10.1186/BF03546704. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Whitaker J R. Principles of Enzymology for the Food Science. New York: Marcel Dekker, Inc.; 1972. p. 332. [Google Scholar]