Stability and specificity of the cell wall-associated poteinase from Lactococcus lactis subsp. cremoris H2 released by treatment with lysozyme in the presence of calcium ions

Article Abstract:

Cells of Lactococcus lactis subsp. cremoris H2 were subjected to lysozyme treatment in the presence of 50 mM calcium chloride. The treatment resulted in the release of three forms of proteinases, having molecular weights of 137-, 145- and 180-kDa, respectively. The former two proteinases were similar to those produced in the absence of calcium ions, and exist as dimers in their native forms. The 180-kDa form, meanwhile, is probably a larger aggregate of the native form. The isolation of these enzymes in the presence of calcium is an important step in establishing correlations between in vitro activity and the in situ process.

Proteases, Lactic acid, Bacteriology Cultures and culture media

---

Specificity of Lactococcus lactis subsp. cremoris SK11 proteinase, lactocepin III, in low-water activity, high-salt-concentration humectant systems and its stability compared with that of lactocepin I

Article Abstract:

A study has revealed that the low-water activity and high-salt-concentration characteristic of cheese imparts lactocepin III characteristics to lactocepin I. The effects of these parameters on the specificity of lactocepin III on the stability of lactocepin I and III were accurately determined. Findings indicate that proteolysis can elucidate certain key factors in cheese flavor development, since proteolytic enzymes are instrumental in the ripening process of most cheeses.

Cheese, Proteolysis, Dairy bacteriology, Humectants

---

Involvement of enzyme-substrate charge interactions in the caseinolytic specificity of lactococcal cell envelope-associated proteinases

Article Abstract:

The nature of interaction between lactococcal cell envelope-associated proteinase (CEP) and caseins during hydrolysis of kappa-casein is complex. Oligopeptides with amino acid sequences similar to the sequence from residue 98 to 111 and from 153 to 169 of kappa-resin exhibited different susceptibilities to P(sub I) and P(sub III) lactococcal proteinases.

Observations, Enzymes, Enzyme regulation, Amino acid sequence, Amino acid sequencing, Milk proteins, Casein

Similar abstracts:

• Abstracts: Cloning and sequencing of pepC, a cysteine aminopeptidase gene from Lactococcus lactis subsp. cremoris AM2
• Abstracts: Cloning and nucleotide sequence of the gene coding for citrate synthase from a thermotolerant Bacillus sp. Role of the Bacillus methanolicus citrate synthase II gene, citY, in regulating the secretion of glutamate in L-lysine-secreting mutants
• Abstracts: Genetic diversity of Xanthomonas oryzae pv. oryzae in Asia. Novel candidate virulence factors in rice pathogen Xanthomonas oryzae pv. oryzicolas as revealed by mutational analysis
• Abstracts: Gene cloning, nucleotide sequencing, and purification and characterization of the low-specificity L-threonine aldolase from Pseudomonas sp. strain NCIMB 10558
• Abstracts: Biochemical and electron microscopic studies of the Streptomyces reticuli cellulase (Avicelase) in its mycelium-associated and extracellular forms

This website is not affiliated with document authors or copyright owners. This page is provided for informational purposes only. Unintentional errors are possible.