Rib类似蛋白在三种乳酸杆菌中的分布

Distribution of Rib like protein in three lactobacilli bacteria

摘要:

【目的】阐明罗伊氏乳杆菌中Rib蛋白在细菌中的亚细胞定位，以及其在几种乳酸杆菌中的分布，探讨Rib蛋白潜在的生物学功能。【方法】以罗伊氏乳杆菌ATCC55730中Rib蛋白的基因为模板，设计特异性引物，通过PCR获得Rib蛋白N末端非重复区序列并在大肠杆菌中进行异源表达，经过亲和层析和分子筛获得纯化的Rib蛋白，制备Rib蛋白的小鼠多克隆抗体。通过蛋白质免疫印迹方法对11株乳酸杆菌中Rib类似蛋白进行检测。【结果】Western blot结果显示Rib蛋白主要分布于罗伊氏乳杆菌的细胞壁上。PCR和Western blot均表明Rib类似蛋白在4株罗伊氏乳杆菌、6株植物乳杆菌和1株干酪乳杆菌中均可被检测到。【结论】Rib类似蛋白可能在乳酸杆菌中分布较广泛，它们主要存在于细菌细胞壁上的现象表明其可能对这些乳杆菌在宿主肠道的定殖具有一定作用。

Abstract:

[Objective] We studied the distribution and potential function of Rib protein, a large bacterial cell surface protein founded in Lactobacillus reuteri, in different lactobacilli strains. [Methods] Primers were designed according to the 5′ non-repeat regain sequence of rib gene in L. reuteri ATCC55730, to PCR rib gene and heterologous expression. Truncated Rib protein from L. reuteri was expressed in Escherichia coli. The recombinant protein was purified and used for polyclonal antibody preparation. Western blot was done in subcellular localization analyses of Rib and Rib like protein detection. [Results] Western blot showed that Rib protein mainly distributed in the L. reuteri bacterial cell wall. Both PCR and Western blot analyses showed that Rib like protein was detected in 11 lactobacilli strains with different size. [Conclusion] Rib like protein is a probable widely distributing cell surface protein in lactobacilli strains, and may play a role in the adhesion of these lactobacilli on the host gut.