ISSN:
1572-9699
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract An extracellular bactericidal substance was isolated from the supernatant of Streptococcus mutans Rm-10 culture fluid and partially purified with 60% ammonium sulfate precipitation, differential centrifugation, and gel filtration on Sephadex G-200. There was a good correlation of the sensitivy profiles of indicator strains whether assayed on solid medium or with purified material from cell-free culture fluid, indicating that the same inhibitory substance is produced on solid medium and in broth. Vapor from organic solvents such as chloroform, acetone, ethanol, and ether as well as heat treatment at 100°C for 30 min had little effect on the bactericidal factor. It was sensitive to trypsin and pronase and resistant to deoxyribonuclease, ribonuclease, lysozyme, and phospholipase C. The inhibitor was not infective, and electron microscopic studies failed to reveal phage or phage-like particles in concentrated solutions of the bactericidal material. The results indicate that the extracellular bactericidal substance is indeed a bacteriocin. Activity in broth cultures reached a maximum only after exponential growth had ceased. It was active against other streptococcal strains as well as strains of Actinomyces naeslundii, A. viscosus, Bacillus subtilis and Staphylococcus aureus, but not against strains of Fusobacterium nucleatum and Escherichia coli.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00457878
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