Identification of Porphyromonas gingivalis proteins secreted by the Por secretion system
Identification of Porphyromonas gingivalis proteins secreted by the Por secretion system
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DOI：
10.1111/1574-6968.12028
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发表时间：
2013-01-01
影响因子：
2.1
通讯作者：
Nakayama, Koji
中科院分区：
文献类型：
--
作者：
Sato, Keiko;Yukitake, Hideharu;Nakayama, Koji
牙龈卟啉单胞菌是一种革兰氏阴性菌，具有多种致病性。特别是，被称为牙龈卟啉菌蛋白酶的半胱氨酸蛋白酶由于其降解宿主蛋白质和加工其他毒力因子如菌毛的能力而受到关注。牙龈蛋白酶通过Por分泌系统（PorSS）易位在细胞表面上或易位到细胞外环境中，PorSS由许多膜或周质蛋白组成，包括PorK、PorL、PorM、PorN、PorO、PorP、PorQ、PorT、PorU、PorV（PG 27、LptO）、PorW和Sov。为了鉴定除了由PorSS分泌的牙龈卟啉菌蛋白酶以外的蛋白质，我们使用二维凝胶电泳和肽质量指纹法比较了牙龈卟啉单胞菌菌株kgp rgpA rgpB（PorSS-熟练菌株）和kgp rgpA rgpB porK（PorSS-缺陷菌株）的蛋白质组。代表10种不同蛋白质的16个斑点存在于PorSS-精通菌株的无颗粒培养物上清液中，但在PorSS-缺陷菌株的无颗粒培养物上清液中不存在或微弱。这些鉴定的蛋白质具有C-末端结构域（CTD），其已被建议形成CTD蛋白家族。这些结果表明PorSS用于分泌除牙龈卟啉菌蛋白酶以外的许多蛋白质，并且蛋白质的CTD与PorSS依赖性分泌相关。
The Gram-negative bacterium Porphyromonas gingivalis possesses a number of potential virulence factors for periodontopathogenicity. In particular, cysteine proteinases named gingipains are of interest given their abilities to degrade host proteins and process other virulence factors such as fimbriae. Gingipains are translocated on the cell surface or into the extracellular milieu by the Por secretion system (PorSS), which consists of a number of membrane or periplasmic proteins including PorK, PorL, PorM, PorN, PorO, PorP, PorQ, PorT, PorU, PorV (PG27, LptO), PorW and Sov. To identify proteins other than gingipains secreted by the PorSS, we compared the proteomes of P. gingivalis strains kgp rgpA rgpB (PorSS-proficient strain) and kgp rgpA rgpB porK (PorSS-deficient strain) using two-dimensional gel electrophoresis and peptide-mass fingerprinting. Sixteen spots representing 10 different proteins were present in the particle-free culture supernatant of the PorSS-proficient strain but were absent or faint in that of the PorSS-deficient strain. These identified proteins possessed the C-terminal domains (CTDs), which had been suggested to form the CTD protein family. These results indicate that the PorSS is used for secretion of a number of proteins other than gingipains and that the CTDs of the proteins are associated with the PorSS-dependent secretion.