Vaccine target and carrier molecule nontypeable Haemophilus influenzae protein D dimerizes like the close Escherichia coli GlpQ homolog but unlike other known homolog dimers.
Vaccine target and carrier molecule nontypeable Haemophilus influenzae protein D dimerizes like the close Escherichia coli GlpQ homolog but unlike other known homolog dimers.
复制标题
疫苗靶标和载体分子不可分型流感嗜血杆菌蛋白 D 像接近的大肠杆菌 GlpQ 同源物一样二聚化，但与其他已知的同源物二聚体不同。
DOI：
10.1002/prot.26418
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发表时间：
2023
期刊：
影响因子：
2.9
通讯作者：
Gleghorn,MichaelL
中科院分区：
文献类型：
--
作者：
Jones,SethP;Cook,KaliH;Holmquist,MelodyL;Almekinder,LiamJ;Delaney,AnnieM;Charles,Ryhl;Labbe,Natalie;Perdue,Janai;Jackson,Niaya;Pichichero,MichaelE;Kaur,Ravinder;Michel,LeaV;Gleghorn,MichaelL
我们已经确定了非脂化（即，N末端截短的）不可分型流感嗜血杆菌（NTHi;流感嗜血杆菌）蛋白D。蛋白D存在于H.流感病毒株，并作为一种毒力因子，帮助入侵人体细胞。蛋白D是在动物模型中治疗阻塞性肺病（COPD）和中耳炎（OM）的经证实的成功抗原，并且当与多糖缀合时也已用作人疫苗的载体分子，例如在GlaxoSmithKline Synflorix™中。NTHi蛋白D与大肠杆菌（Escherichia coli，E. coli）glpQ基因产物（GlpQ）。coliGlpQ是甘油磷酸二酯磷酸二酯酶（GDPD），在蛋白质结构数据库中具有已知的二聚体结构，尽管没有相关的出版物。我们在这里表明，这两种结构表现出类似的同型二聚体组织，尽管略有不同的晶格。此外，我们已经观察到在尺寸排阻色谱（SEC）实验期间溶液中存在弱二聚化和缺乏二聚化，但在天然质谱分析中明显观察到二聚化。NTHi蛋白D和E的比较。coliGlpQ与其它同源二聚体和单体的同源性分析表明，E.大肠杆菌和NTHi同源二聚体界面是不同的。尽管有这种区别，NTHi蛋白D和E。coliGlpQ具有在许多其他同源物中看到的丙糖磷酸异构酶（TIM）桶结构域。NTHi蛋白D的活性位点位于该TIM桶的中心附近。一个假定的甘油部分建模在两个不同的构象（occupational）在我们的NTHi蛋白D结构的活性位点，我们比较了这与配体建模在同源结构。我们的结构分析应有助于在未来的努力，以确定蛋白D结合底物，类似物中间体和产品的结构，充分认识到这一反应方案，并在未来的抑制剂设计援助。
We have determined the 1.8 Å X‐ray crystal structure of nonlipidated (i.e., N‐terminally truncated) nontypeableHaemophilus influenzae(NTHi;H.influenzae) protein D. Protein D exists on outer membranes ofH. influenzaestrains and acts as a virulence factor that helps invade human cells. Protein D is a proven successful antigen in animal models to treat obstructive pulmonary disease (COPD) and otitis media (OM), and when conjugated to polysaccharides also has been used as a carrier molecule for human vaccines, for example in GlaxoSmithKline Synflorix™. NTHi protein D shares high sequence and structural identify to theEscherichia coli(E. coli)glpQgene product (GlpQ).E. coliGlpQ is a glycerophosphodiester phosphodiesterase (GDPD) with a known dimeric structure in the Protein Structural Database, albeit without an associated publication. We show here that both structures exhibit similar homodimer organization despite slightly different crystal lattices. Additionally, we have observed both the presence of weak dimerization and the lack of dimerization in solution during size exclusion chromatography (SEC) experiments yet have distinctly observed dimerization in native mass spectrometry analyses. Comparison of NTHi protein D andE. coliGlpQ with other homologous homodimers and monomers shows that theE. coliand NTHi homodimer interfaces are distinct. Despite this distinction, NTHi protein D andE. coliGlpQ possess a triose‐phosphate isomerase (TIM) barrel domain seen in many of the other homologs. The active site of NTHi protein D is located near the center of this TIM barrel. A putative glycerol moiety was modeled in two different conformations (occupancies) in the active site of our NTHi protein D structure and we compared this to ligands modeled in homologous structures. Our structural analysis should aid in future efforts to determine structures of protein D bound to substrates, analog intermediates, and products, to fully appreciate this reaction scheme and aiding in future inhibitor design.