Structure-function analysis for the development of peptide inhibitors for a Gram-positive quorum sensing system.
Structure-function analysis for the development of peptide inhibitors for a Gram-positive quorum sensing system.
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DOI：
10.1111/mmi.14921
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发表时间：
2022-06
影响因子：
3.6
通讯作者：
Yesilkaya, Hasan
中科院分区：
文献类型：
--
作者：
Abdullah, Iman Tajer;Ulijasz, Andrew T.;Girija, Umakhanth Venkatraman;Tam, Sien;Andrew, Peter;Hiller, Natalia Luisa;Wallis, Russell;Yesilkaya, Hasan
关键词：
肺炎链球菌 Rgg144/SHP144 调节肽群体感应 (QS) 系统对于营养利用、氧化应激反应和毒力至关重要。在这里，我们通过丙氨酸扫描诱变评估活性短疏水肽（SHP）中每个残基的重要性并测试所得肽的受体结合和受体激活来表征该系统。有趣的是，一些突变对与 Rgg144 的结合几乎没有影响，但明显降低了转录激活。特别是，脯氨酸取代 (P21A) 将转录激活降低了 29 倍，但结合亲和力比野生型 SHP 高 3 倍。与 Rgg144 的功能一致，突变肽导致甘露糖利用率降低，并增加对超氧化物产生剂百草枯的敏感性。全基因组比较显示 SHP144 等位基因变体中 P21 完全保守。在不存在肽的情况下，Rgg144 的结晶揭示了与其同系物的 DNA 结合形式和游离形式相当的结构，表明类似的激活机制。这些分析共同确定了关键肺炎球菌 QS 系统中的关键相互作用。对 SHP 的进一步操作有可能促进跨菌株发挥功能的抑制剂的开发。这里描述的方法可能在多个物种的 QS 系统中有效。 肺炎链球菌利用细胞间通讯分子网络来响应细胞外信号。调节肽系统 Rgg144/SHP144 在该网络中发挥着核心作用，使其成为主要的毒力决定因素。在这里，我们采用结构功能研究来鉴定有助于 Rgg144 信号的亲和力和活性的残基，进而调节肺炎球菌的发病机制。
The Streptococcus pneumoniae Rgg144/SHP144 regulator‐peptide quorum sensing (QS) system is critical for nutrient utilization, oxidative stress response, and virulence. Here, we characterized this system by assessing the importance of each residue within the active short hydrophobic peptide (SHP) by alanine‐scanning mutagenesis and testing the resulting peptides for receptor binding and activation of the receptor. Interestingly, several of the mutations had little effect on binding to Rgg144 but reduced transcriptional activation appreciably. In particular, a proline substitution (P21A) reduced transcriptional activation by 29‐fold but bound with a 3‐fold higher affinity than the wild‐type SHP. Consistent with the function of Rgg144, the mutant peptide led to decreased utilization of mannose and increased susceptibility to superoxide generator paraquat. Pangenome comparison showed full conservation of P21 across SHP144 allelic variants. Crystallization of Rgg144 in the absence of peptide revealed a comparable structure to the DNA bound and free forms of its homologs suggesting similar mechanisms of activation. Together, these analyses identify key interactions in a critical pneumococcal QS system. Further manipulation of the SHP has the potential to facilitate the development of inhibitors that are functional across strains. The approach described here is likely to be effective across QS systems in multiple species. Streptococcus pneumoniae utilizes a network of cell‐cell communication molecules to respond to extracellular cues. The regulator‐peptide system, Rgg144/SHP144, plays a central role in this network, making it a major virulence determinant. Here we employ structure‐function studies to identify residues that contribute to the affinity and activities of Rgg144 signalling that in turn modulate pneumococcal pathogenesis.
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影响因子：
6.7
作者：
Kahya HF;Andrew PW;Yesilkaya H
通讯作者：
Yesilkaya H
影响因子：
5.2
作者：
Perez-Pascual D;Monnet V;Gardan R
通讯作者：
Gardan R
影响因子：
8
作者：
Hong, L;Zhang, XJC;Tang, J
通讯作者：
Tang, J
DOI：
10.1107/s0907444905001307
发表时间：
2005-04-01
影响因子：
2.2
作者：
Panjikar, S;Parthasarathy, V;Tucker, PA
通讯作者：
Tucker, PA
影响因子：
4.8
作者：
Aggarwal, Chaitanya;Jimenez, Juan Cristobal;Federle, Michael J.
通讯作者：
Federle, Michael J.