Common Oral Diseases and Epidemiology Research Center and the Department of Stomatology, Faculty of Dentistry, Prince of Songkla University, Hat-Yai 90112, Thailand.
Common Oral Diseases and Epidemiology Research Center and the Department of Preventive Dentistry, Faculty of Dentistry, Prince of Songkla University Hat-Yai 90112, Thailand.
Anaerobe. 2014 Jun;27:17-21. doi: 10.1016/j.anaerobe.2014.03.001. Epub 2014 Mar 15.
The present study aimed to purify and characterize the antimicrobial protein from Lactobacillus paracasei SD1, which is a strain from the human oral cavity. Antimicrobial activity was obtained from purifying the culture supernatant of L. paracasei SD1. Purification of the active compound was achieved with ammonium sulfate precipitation followed by chloroform and gel filtration chromatography. As revealed by SDS-PAGE, the active fraction was homogeneous, showing a protein with an approximate molecular weight of 25,000 Da. It was confirmed as having a molecular mass of 24,028.2 Da by mass spectrometry. The antimicrobial compound, named "paracasin SD1", exhibited a broad spectrum against oral pathogens. Paracasin SD1 was stable in a pH range between 3.0 and 8.0 at 100 °C for 5 min, and showed resistance to α-amylase, catalase, lysozyme and whole saliva. However, its activity was lost after proteinase K and trypsin treatment. The results obtained suggest the possibility of using paracasin SD1 for application in prevention/treatment of oral diseases.
本研究旨在从人体口腔来源的乳杆菌 SD1 中纯化和鉴定其具有抗菌活性的蛋白质。从乳杆菌 SD1 的培养上清液中获得抗菌活性。采用硫酸铵沉淀、氯仿抽提和凝胶过滤层析对活性化合物进行纯化。SDS-PAGE 结果显示，活性部分为均一的蛋白，分子量约为 25000 Da。质谱分析确定其分子量为 24028.2 Da。该抗菌化合物命名为“paracasin SD1”，对口腔病原菌具有广谱抗菌活性。Paracasin SD1 在 pH 值为 3.0 至 8.0 之间、100°C 下 5 分钟内稳定，对α-淀粉酶、过氧化氢酶、溶菌酶和全唾液具有抗性。然而，经蛋白酶 K 和胰蛋白酶处理后，其活性丧失。研究结果提示，paracasin SD1 有可能用于预防和治疗口腔疾病。
