Key Laboratory of Animal Protein Deep Processing Technology of Zhejiang Province, Marine Science School, Ningbo University, Ningbo, P. R. China.
Department of Food Science and Nutrition, Jinling College, Nanjing Normal University, Nanjing, P.R. China.
Proteomics. 2018 Mar;18(5-6):e1700308. doi: 10.1002/pmic.201700308.
Many health effects of Lactobacillus acidophilus are desirable among these the adhesion ability is vital to enhance the possibility of colonization and stabilization associated with the gut mucosal barrier. In this study, the growth characteristics and the adhesion activity of L. acidophilus in the intestine-like pH environment (pH 7.5) are identified. The number of bacteria adhering to the HT-29 cells is found with a gradual increase trend (pH 5.5-7.5). This also leads to the morphological changes of L. acidophilus after exposure to different pH environments. Furthermore, with the help of the isobaric tags for relative and absolute quantification (iTRAQ) proteomic analysis, 207 proteins are detected differentially expressed at pH of 7.5. The use of GO analysis and KEGG analysis indicates three essential pathways related to the cell envelope peptide-glycan biosynthesis, carbohydrate metabolism, and amino acid metabolism are obviously changed. Adhesion related surface protein fmtB and PrtP are upregulated in pH 7.5 group. While the moonlight proteins like pyruvate kinase, which binds specifically to the mucin layer and inhibits the adhesive activity of L. acidophilus, is found downregulated. These results could be useful to understand the adhesion mechanism of L. acidophilus adapting for the gut mucosal barrier in the intestinal environment.
嗜酸乳杆菌的许多健康影响在这些影响中是理想的，其中粘附能力对于增强与肠道黏膜屏障相关的定植和稳定的可能性至关重要。在本研究中，确定了嗜酸乳杆菌在类似肠道 pH 环境（pH 7.5）中的生长特性和粘附活性。发现粘附到 HT-29 细胞的细菌数量呈逐渐增加的趋势（pH 5.5-7.5）。这也导致嗜酸乳杆菌在暴露于不同 pH 环境后形态发生变化。此外，借助相对和绝对定量同位素标记技术（iTRAQ）蛋白质组学分析，在 pH 7.5 时检测到 207 种差异表达的蛋白质。GO 分析和 KEGG 分析的使用表明，与细胞包膜肽聚糖生物合成、碳水化合物代谢和氨基酸代谢相关的三个重要途径明显改变。粘附相关表面蛋白 fmtB 和 PrtP 在 pH 7.5 组中上调。而像丙酮酸激酶这样的月光蛋白，它特异性地结合到粘蛋白层并抑制嗜酸乳杆菌的粘附活性，则发现下调。这些结果有助于理解嗜酸乳杆菌适应肠道黏膜屏障的粘附机制在肠道环境中。
