Goetting-Minesky M Paula, Godovikova Valentina, Fenno J Christopher
Department of Biologic and Materials Sciences & Prosthodontics, School of Dentistry, University of Michigan, Ann Arbor, MI, United States.
Front Cell Infect Microbiol. 2021 May 18;11:668287. doi: 10.3389/fcimb.2021.668287. eCollection 2021.
The oral spirochete is a keystone periodontal pathogen that, in association with members of a complex polymicrobial oral biofilm, contributes to tissue damage and alveolar bone loss in periodontal disease. Virulence-associated behaviors attributed to include disruption of the host cell extracellular matrix, tissue penetration and disruption of host cell membranes accompanied by dysregulation of host immunoregulatory factors. dentilisin is associated with several of these behaviors. Dentilisin is an outer membrane-associated complex of acylated subtilisin-family PrtP protease and two other lipoproteins, PrcB and PrcA, that are unique to oral spirochetes. Dentilisin is encoded in a single operon consisting of -. We employ multiple approaches to study mechanisms of dentilisin assembly and PrtP protease activity. To determine the role of each protein in the protease complex, we have made targeted mutations throughout the protease locus, including polar and nonpolar mutations in each gene (, , ) and deletions of specific PrtP domains, including single base mutagenesis of key PrtP residues. These will facilitate distinguishing between host cell responses to dentilisin protease activity and its acyl groups. The boundaries of the divergent promoter region and the relationship between dentilisin and the adjacent iron transport operon are being resolved by incremental deletions in the sequence immediately 5' to the protease locus. Comparison of the predicted three-dimensional structure of PrtP to that of other subtilisin-like proteases shows a unique PrtP C-terminal domain of approximately 250 residues. A survey of global gene expression in the presence or absence of protease gene expression reveals potential links between dentilisin and iron uptake and homeostasis in . Understanding the mechanisms of dentilisin transport, assembly and activity of this unique protease complex may lead to more effective prophylactic or therapeutic treatments for periodontal disease.
口腔螺旋体是一种关键的牙周病原体，它与复杂的多微生物口腔生物膜中的成员共同作用，导致牙周疾病中的组织损伤和牙槽骨丧失。归因于它的毒力相关行为包括破坏宿主细胞外基质、组织穿透以及破坏宿主细胞膜，并伴有宿主免疫调节因子的失调。牙本质素与其中几种行为有关。牙本质素是一种与外膜相关的复合物，由酰化枯草杆菌蛋白酶家族的PrtP蛋白酶和另外两种脂蛋白PrcB和PrcA组成，这两种脂蛋白是口腔螺旋体所特有的。牙本质素由一个由 - 组成的单一操纵子编码。我们采用多种方法来研究牙本质素组装和PrtP蛋白酶活性的机制。为了确定每种蛋白质在蛋白酶复合物中的作用，我们在整个蛋白酶基因座上进行了靶向突变，包括每个基因中的极性和非极性突变（，，）以及特定PrtP结构域的缺失，包括关键PrtP残基的单碱基诱变。这些将有助于区分宿主细胞对牙本质素蛋白酶活性及其酰基的反应。通过在蛋白酶基因座5'端紧邻的序列中进行逐步缺失，正在解析不同启动子区域的边界以及牙本质素与相邻铁转运操纵子之间的关系。将PrtP的预测三维结构与其他枯草杆菌蛋白酶样蛋白酶的结构进行比较，发现了一个约250个残基的独特PrtP C末端结构域。在有或没有蛋白酶基因表达的情况下对全局基因表达进行的调查揭示了牙本质素与铁摄取和体内稳态之间的潜在联系。了解这种独特蛋白酶复合物的牙本质素转运、组装和活性机制可能会导致对牙周疾病更有效的预防或治疗方法。
