Characterization of the pattern of αs1- and β-casein breakdown and release of a bioactive peptide by a cell envelope proteinase from Lactobacillus delbrueckii subsp lactis CRL 581"
Characterization of the pattern of αs1- and β-casein breakdown and release of a bioactive peptide by a cell envelope proteinase from Lactobacillus delbrueckii subsp lactis CRL 581"
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DOI：
10.1128/aem.00247-08
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发表时间：
2008-06-01
影响因子：
4.4
通讯作者：
Addeo, Francesco
中科院分区：
文献类型：
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作者：
Hebert, Elvira Maria;Mamone, Gianfranco;Addeo, Francesco
乳酸杆菌的细胞凋亡相关蛋白酶（CEPs）在细菌营养中起关键作用，并且还有助于发酵乳制品的感官特性的发展，因为它们可以从乳蛋白中释放生物活性的有益健康的肽。研究了不同肽源、不同糖源和不同渗透压对干酪发酵剂德氏乳杆菌CEP活性的影响。lactis CRL 581进行了研究。CEP活性水平由生长培养基的肽含量控制。在基础最小限定培养基中观察到最大活性，而在Casitone、酪蛋白氨基酸或酵母提取物的存在下，CEP的合成分别被抑制99倍、70倍和68倍。添加特定的二肽或三肽含有支链氨基酸，如亮氨酰亮氨酸，脯氨酰亮氨酸，亮氨酰glycylglycine，或亮氨酰脯氨酸，到生长培养基中产生负面影响CEP活性，而二肽没有支链氨基酸对酶的生产没有影响。碳源和渗透剂对CEP活性无影响。L.德氏乳酸菌CRL 581表现出混合型CEPI/III变体酪蛋白溶解特异性。通过反相高压液相色谱法分离的主要肽峰的质谱筛选允许在α（S1）-和β-酪蛋白水解产物中分别鉴定33和32种肽。通过对这些水解产物中的肽序列进行表征，确定了α（s1）-和β-酪蛋白分解的模式，并在本文中报道，这是对L.德氏乳酸菌。在这种模式下，一系列潜在的生物活性肽（抗高血压和磷酸肽），这是加密的前体蛋白可以可视化。
The cell envelope-associated proteinases (CEPs) of the lactobacilli have key roles in bacterial nutrition and contribute to the development of the organoleptic properties of fermented milk products as well, as they can release bioactive health-beneficial peptides from milk proteins. The influence of the peptide supply, carbohydrate source, and osmolites on the CEP activity of the cheese starter Lactobacillus delbrueckii subsp. lactis CRL 581 was investigated. The CEP activity levels were controlled by the peptide content of the growth medium. The maximum activity was observed in a basal minimal defined medium, whereas in the presence of Casitone, Casamino Acids, or yeast extract, the synthesis of CEP was inhibited 99-, 70-, and 68-fold, respectively. The addition of specific di- or tripeptides containing branched-chain amino acids, such as leucylleucine, prolyllleucine, leucylglycylglycine, or leucylproline, to the growth medium negatively affected CEP activity, whereas dipeptides without branched-chain amino acids had no effect on the enzyme's production. The carbon source and osmollites did not affect CEP activity. The CEP of L. delbrueckii subsp. lactis CRL 581 exhibited a mixed-type CEPI/III variant caseinolytic specificity. Mass-spectrometric screening of the main peptide peaks isolated by reverse-phase high-pressure liquid chromatography allowed the identification of 33 and 32 peptides in the alpha(s1)- and beta-casein hydrolysates, respectively. By characterizing the peptide sequence in these hydrolysates, a pattern of alpha(s1)- and beta-casein breakdown was defined and is reported herein, this being the first report for a CEP of L. delbrueckii subsp. lactis. In this pattern, a series of potentially bioactive peptides (antihypertensive and phosphopeptides) which are encrypted within the precursor protein could be visualized.