Functional Analysis of the p40 and p75 Proteins from Lactobacillus casei BL23
Functional Analysis of the p40 and p75 Proteins from Lactobacillus casei BL23
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DOI：
10.1159/000322233
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发表时间：
2010-01-01
影响因子：
1.2
通讯作者：
Monedero, Vicente
中科院分区：
文献类型：
--
作者：
Baeuerl, Christine;Perez-Martinez, Gaspar;Monedero, Vicente
干酪乳杆菌/副干酪乳杆菌和鼠李糖乳杆菌菌株的基因组携带编码来自L. rhamnosus GG，两种对人肠上皮细胞显示抗凋亡和细胞保护作用的分泌蛋白。p40和p75分别携带半胱氨酸、组胺依赖性氨基水解酶/肽酶（CHAP）和NLPC/P60结构域，这些结构域是具有细胞壁水解酶活性的蛋白质的特征。在洛casei BL 23两种蛋白质都分泌到生长培养基中，并且也位于细菌细胞表面。编码这两种蛋白质的基因在该菌株中失活。LCABL_00230（编码p40）的失活没有导致表型的显著差异，而LCABL_02770（编码p75）的突变产生形成非常长链的细胞。纯化的谷胱甘肽-S-转移酶（GST）-p40和-p75融合蛋白能水解L.干酪细胞壁。两种融合蛋白均与粘蛋白、胶原蛋白和肠上皮细胞结合，与L. rhamnosus GG p40刺激小鼠肠中离体表皮生长因子受体磷酸化。这些结果表明，属于细胞壁代谢机制的胞外蛋白质在密切相关的L。干酪/副干酪-L. rhamnosus组最有可能涉及针对这些细菌描述的益生菌作用。Karger AG，巴塞尔
The genomes of Lactobacillus casei/paracasei and Lactobacillus rhamnosus strains carry two genes encoding homologues of p40 and p75 from L. rhamnosus GG, two secreted proteins which display anti-apoptotic and cell protective effects on human intestinal epithelial cells. p40 and p75 carry cysteine, histidine-dependent aminohydrolase/peptidase (CHAP) and NLPC/P60 domains, respectively, which are characteristic of proteins with cell-wall hydrolase activity. In L. casei BL23 both proteins were secreted to the growth medium and were also located at the bacterial cell surface. The genes coding for both proteins were inactivated in this strain. Inactivation of LCABL_00230 (encoding p40) did not result in a significant difference in phenotype, whereas a mutation in LCABL_02770 (encoding p75) produced cells that formed very long chains. Purified glutathione-S-transferase (GST)-p40 and -p75 fusion proteins were able to hydrolyze the muropeptides from L. casei cell walls. Both fusions bound to mucin, collagen and to intestinal epithelial cells and, similar to L. rhamnosus GG p40, stimulated epidermal growth factor receptor phosphorylation in mouse intestine ex vivo. These results indicate that extracellular proteins belonging to the machinery of cell-wall metabolism in the closely related L. casei/paracasei-L. rhamnosus group are most likely involved in the probiotic effects described for these bacteria Copyright (C) 2010 S. Karger AG, Basel