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. 1985 Feb;49(2):328–332. doi: 10.1128/aem.49.2.328-332.1985

Partial Isolation and Degradation of Caseins by Cell Wall Proteinase(s) of Streptococcus cremoris HP

Fred A Exterkate 1,*, Gerrie J C M de Veer 1
PMCID: PMC238402  PMID: 16346719

Abstract

The cell wall proteinase fraction of Streptococcus cremoris HP has been isolated. This preparation did not exhibit any activity due to either specific peptidases known to be located near the outside surface of and in the membrane or intracellular proteolytic enzymes. By using thin-layer chromatography for the detection of relatively small hydrolysis products which remain soluble at pH 4.6, it was shown that β-casein is preferentially attacked by the cell wall proteinase. This was also the case when whole casein or micelles were used as the substrate. κ-casein hydrolysis is a relatively slow process, and αs-casein degradation appeared to proceed at an extremely low rate. These results could be confirmed by using 14CH3-labeled caseins. A relatively fast and linear initial progress of 14CH3-labeled β-casein degradation is not inhibited by αs-casein and only slightly by κ-casein at concentrations of these components which reflect their stoichiometry in the micelles. Possible implications of β-casein degradation for growth of the organism in milk are discussed.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Argyle P. J., Mathison G. E., Chandan R. C. Production of cell-bound proteinase by Lactobacillus bulgaricus and its location in the bacterial cell. J Appl Bacteriol. 1976 Aug;41(1):175–184. doi: 10.1111/j.1365-2672.1976.tb00616.x. [DOI] [PubMed] [Google Scholar]
  2. Bradford M. M. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 1976 May 7;72:248–254. doi: 10.1016/0003-2697(76)90527-3. [DOI] [PubMed] [Google Scholar]
  3. Exterkate F. A. Location of Peptidases Outside and Inside the Membrane of Streptococcus cremoris. Appl Environ Microbiol. 1984 Jan;47(1):177–183. doi: 10.1128/aem.47.1.177-183.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Law B. A., Kolstad J. Proteolytic systems in lactic acid bacteria. Antonie Van Leeuwenhoek. 1983 Sep;49(3):225–245. doi: 10.1007/BF00399500. [DOI] [PubMed] [Google Scholar]
  5. MCDONALD I. J. Utilization of sodium caseinate by lactic streptococci and enterococci. Can J Microbiol. 1956 Oct;2(6):607–610. doi: 10.1139/m56-073. [DOI] [PubMed] [Google Scholar]
  6. Ohmiya K., Sato Y. Purification and Properties of Intracellular Proteinase from Streptococcus cremoris. Appl Microbiol. 1975 Nov;30(5):738–745. doi: 10.1128/am.30.5.738-745.1975. [DOI] [PMC free article] [PubMed] [Google Scholar]

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