Laboratorio de Patogénesis Microbiana, Centro de Investigaciones Biológicas del Noroeste, La Paz, Baja California Sur, México.
J Appl Microbiol. 2009 Dec 1;107(6):1866-74. doi: 10.1111/j.1365-2672.2009.04368.x. Epub 2009 May 5.
To identify and characterize adhesion-associated proteins in the potential probiotic Lactobacillus fermentum BCS87.
Protein suspensions obtained from the treatment of Lact. fermentum BCS87 with 1 mol 1(-1) LiCl were analysed by Western blotting using HRP-labelled porcine mucus and mucin. Two adhesion-associated proteins with relative molecular weight of 29 and 32 kDa were identified. The N-terminal and internal peptides of the 32 kDa protein (32-Mmubp) were sequenced, and the corresponding gene (32-mmub) was found by inverse polymerase chain reaction. The complete nucleotide sequence of 32-mmub revealed an open reading frame of 903 bp encoding a primary protein of 300 amino acids and a mature protein of 272 residues. A basic local alignment search showed 47-99% identity to solute-binding components of ATP binding cassette transporter proteins in Lactobacillus, Streptococcus and Clostridium. An OpuAC-conserved domain was identified and phylogenetic relationship analysis confirmed that 32-Mmubp belongs to the OpuAC family.
Adhesion of Lact. fermentum BCS87 appeared to be mediated by two surface-associated proteins. 32-Mmubp is a component of ABC transporter system that also functions as an adhesin.
Characterization of 32-Mmubp and 32-mmub will contribute to understanding the host-bacteria interactions of Lact. fermentum with the intestinal tract of pigs.
鉴定并分析潜在益生菌发酵乳杆菌 BCS87 中的黏附相关蛋白。
采用 HRP 标记的猪黏液和黏蛋白对用 1 mol/L LiCl 处理的发酵乳杆菌 BCS87 进行 Western blot 分析，得到蛋白悬浮液。鉴定出两种相对分子质量分别为 29 和 32 kDa 的黏附相关蛋白。对 32 kDa 蛋白（32-Mmubp）的 N 末端和内部肽进行测序，并通过反向聚合酶链反应发现相应基因（32-mmub）。32-mmub 的完整核苷酸序列显示，其开放阅读框长 903 bp，编码一个由 300 个氨基酸组成的初级蛋白和一个由 272 个残基组成的成熟蛋白。基本局部比对搜索显示，其与乳杆菌、链球菌和梭菌中 ATP 结合盒转运蛋白的溶质结合成分具有 47%-99%的同一性。鉴定出一个 OpuAC 保守结构域，系统发育关系分析证实 32-Mmubp 属于 OpuAC 家族。
发酵乳杆菌 BCS87 的黏附作用似乎由两种表面相关蛋白介导。32-Mmubp 是 ABC 转运系统的一个组成部分，也作为黏附素发挥作用。
32-Mmubp 的特性分析和 32-mmub 的鉴定将有助于理解发酵乳杆菌与猪肠道的宿主-细菌相互作用。
