LISM, Institut de Microbiologie de la Méditerranée, CNRS and Aix-Marseille University, France.
NMR Platform, Institut de Microbiologie de la Méditerranée, CNRS and Aix-Marseille University, France.
FEBS Lett. 2020 Jan;594(2):251-265. doi: 10.1002/1873-3468.13593. Epub 2019 Sep 21.
Salmonella is a facultative intracellular pathogen that invades epithelial cells of the intestine using the SPI-1 Type 3 secretion System (T3SS). Insertion of the SPI-1 T3SS translocon is facilitated by acylation of the translocator SipB, which involves a protein-protein interaction with the acyl carrier protein IacP. Using nuclear magnetic resonance and biological tests, we identified the residues of IacP that are involved in the interaction with SipB. Our results suggest that the 4'-phosphopantetheine group that functionalizes IacP participates in the interaction. Its solvent exposition may rely on two residues highly conserved in acyl carrier proteins associated with T3SS. This study is the first to address the specificity of acyl carrier proteins associated with T3SS.
沙门氏菌是一种兼性细胞内病原体，它使用 SPI-1 型 III 型分泌系统（T3SS）入侵肠道的上皮细胞。SPI-1 T3SS 转位器的插入是由转位器 SipB 的酰化作用促进的，这涉及到与酰基载体蛋白 IacP 的蛋白-蛋白相互作用。通过核磁共振和生物测试，我们确定了 IacP 与 SipB 相互作用的残基。我们的结果表明，赋予 IacP 功能的 4'-磷酸泛酰巯基乙胺基团参与了相互作用。其溶剂暴露可能依赖于与 T3SS 相关的酰基载体蛋白中高度保守的两个残基。这项研究首次解决了与 T3SS 相关的酰基载体蛋白的特异性问题。
