Yang Pei-Jin, Zhan Ming-Yue, Yang Li-Ling, Liu Qiong-Qiong, Xu Yang, Pan Yue-Min, Rao Xiang-Jun
School of Plant Protection, Anhui Agricultural University, Hefei, Anhui, 230036, China.
Biotechnology Center, Anhui Agricultural University, Hefei, Anhui, 230036, China.
Dev Comp Immunol. 2019 Jan;90:121-129. doi: 10.1016/j.dci.2018.09.009. Epub 2018 Sep 15.
Peptidoglycan is the key component forming the backbone of bacterial cell wall. It can be recognized by a group of pattern recognition receptors, known as peptidoglycan recognition proteins (PGRPs) in insects and higher animals. PGRPs may serve as immune receptors or N-acetylmuramoyl-L-alanine amidases (EC 3.5.1.28). Here, we report the characterization of a short PGRP, PGRP-S1, from the oriental armyworm, Mythimna separata. MsePGRP-S1 cDNA encodes a protein of 197 amino acids (aa) with a PGRP domain of about 150 aa. MsePGRP-S1 was expressed in several tissues of naïve larvae, including hemocytes, midgut, fat body and epidermis. Bacterial challenges caused variable changes in different tissues at the mRNA level. The recombinant protein bound strongly to Staphylococcus aureus and purified peptidoglycans from Staphylococcus aureus and Bacillus subtilis. It can inhibit the growth of gram-negative and gram-positive bacteria by disrupting bacterial surface. It can degrade peptidoglycans from Escherichia coli and Staphylococcus aureus. Taken together, these data demonstrate that M. separata PGRP-S1 is involved in defending against bacteria.
肽聚糖是构成细菌细胞壁骨架的关键成分。它能被一组模式识别受体识别，在昆虫和高等动物中这些受体被称为肽聚糖识别蛋白（PGRPs）。PGRPs可能作为免疫受体或N - 乙酰胞壁酰 - L - 丙氨酸酰胺酶（EC 3.5.1.28）。在此，我们报道了从东方粘虫（Mythimna separata）中鉴定出的一种短肽聚糖识别蛋白PGRP - S1的特性。MsePGRP - S1 cDNA编码一个由197个氨基酸（aa）组成的蛋白质，带有一个约150个aa的PGRP结构域。MsePGRP - S1在未受感染幼虫的多个组织中表达，包括血细胞、中肠、脂肪体和表皮。细菌刺激在mRNA水平上导致不同组织发生不同变化。重组蛋白与金黄色葡萄球菌以及从金黄色葡萄球菌和枯草芽孢杆菌中纯化的肽聚糖强烈结合。它可以通过破坏细菌表面来抑制革兰氏阴性菌和革兰氏阳性菌的生长。它可以降解大肠杆菌和金黄色葡萄球菌的肽聚糖。综上所述，这些数据表明东方粘虫PGRP - S1参与抵御细菌。
