[从噬菌体展示肽库中筛选鼠伤寒沙门氏菌脂多糖模拟表位]

[Screening of mimotope of Salmonella typhimurium lipopolysaccharide from phage-displayed peptide].

作者信息

Zheng Shan-gen, Zhu Ping, Liu Bei-yi, Fu Ning

机构信息

Department of Immunology, First Military Medical University, Guangzhou 510515, China.

出版信息

Di Yi Jun Yi Da Xue Xue Bao. 2003 Feb;23(2):118-20, 123.

PMID:12581956

Abstract

OBJECTIVE

To identify and characterize the mimotope of lipopolysaccharide (LPS) from cyclic 7-mer phage peptide library.

METHODS

Cyclic 7-mer phage-displayed peptide library was screened using monoclonal antibody 2F4 (mAb 2F4) against Salmonella typhimurium LPS as the target, and the selected clones were tested by sandwich enzyme-linked immunosorbent assay (ELISA) and specific antigen inhibition ELISA.

RESULTS

After 3 round of screening, 34 of the 38 selected clones were identified as positive for binding to mAb 2F4. Salmonella typhimurium LPS was capable of inhibiting the binding between the cones and mAb 2F4, with the 50% inhibitory concentration of all the positive clones within the range of 0.125-0.250 microg/ml. Sequence analysis was performed for 10 of the positive clones, whose amino acid sequences were subsequently deduced, and 7 of them had conservative amino acid of P-X-WAS-X-W with the mean hydrophobic amino acid content of 71.4% in all the sequences.

CONCLUSION

The phage-displayed peptide is capable of simulating the epitope of Salmonella typhimurium LPS.

摘要

目的

从环状七肽噬菌体肽库中鉴定和表征脂多糖（LPS）的模拟表位。

方法

以抗鼠伤寒沙门氏菌LPS的单克隆抗体2F4（mAb 2F4）为靶标筛选环状七肽噬菌体展示肽库，并用夹心酶联免疫吸附测定法（ELISA）和特异性抗原抑制ELISA对筛选出的克隆进行检测。

结果

经过三轮筛选，38个筛选出的克隆中有34个被鉴定为与mAb 2F4结合呈阳性。鼠伤寒沙门氏菌LPS能够抑制克隆与mAb 2F4之间的结合，所有阳性克隆的50%抑制浓度在0.125 - 0.250微克/毫升范围内。对10个阳性克隆进行了序列分析，随后推导其氨基酸序列，其中7个具有保守氨基酸P-X-WAS-X-W，所有序列中平均疏水氨基酸含量为71.4%。