Active S2168 and inactive S21IRS pinholin interact differently with the lipid bilayer: A 31P and 2H solid state NMR study
Active S2168 and inactive S21IRS pinholin interact differently with the lipid bilayer: A 31P and 2H solid state NMR study
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DOI：
10.1016/j.bbamem.2020.183257
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发表时间：
2020-07-01
影响因子：
3.4
通讯作者：
Lorigan, Gary A.
中科院分区：
文献类型：
--
作者：
Drew, Daniel L., Jr.;Butcher, Brandon;Lorigan, Gary A.
Pinholins是一个裂解膜蛋白家族，负责裂解双链DNA噬菌体宿主细胞的细胞膜。蛋白质-脂质相互作用不仅影响膜蛋白的功能，而且影响膜蛋白的拓扑结构。本工作研究了针孔蛋白在活性和非活性确认中与磷脂双层之间的相互作用，以阐明这两种形式与双层之间的不同相互作用。将Pinholin掺入氚DMPC-d(54)脂双层膜中，结合P-31和H-2固体核磁共振(SS-核磁共振)谱研究了蛋白质-脂类与双层膜表面磷头基团的相互作用，并利用与H-2核的相互作用研究了疏水核心区。比较活性的S(21)68针孔蛋白和非活性的(SIRS)-I-21针孔蛋白的P-31化学位移各向异性(CsA)值表明，与非活性形式的针孔蛋白相比，活性形式的针孔蛋白具有更强的头基相互作用，支持活性的S(21)68的部分外化的外周跨膜结构域的模型，而不是Ahammad等人提出的完全外化的TMD1。2019年少年警讯B。H-2四极分裂分析表明，在所有温度下，这两种形式的针孔蛋白的光谱宽度都比空双分子层的光谱宽度减小。在这种情况下，非活性(SIRS)-I-21形式的Pinholin的光谱宽度的减少表明与双层的酰基链有更强的相互作用。H-2核磁共振谱中观察到的峰分辨率的损失支持了膜内存在非活性形式的额外的TMD。
Pinholins are a family of lytic membrane proteins responsible for the lysis of the cytosolic membrane in host cells of double stranded DNA bacteriophages. Protein-lipid interactions have been shown to influence membrane protein topology as well as its function. This work investigated the interactions of pinholin with the phospholipid bilayer while in active and inactive confirmations to elucidate the different interactions the two forms have with the bilayer. Pinholin incorporated into deuterated DMPC-d(54) lipid bilayers, along with P-31 and H-2 solid state NMR (SS-NMR) spectroscopy were used to probe the protein-lipid interactions with the phosphorus head group at the surface of the bilayer while interactions with the H-2 nuclei were used to study the hydrophobic core. A comparison of the P-31 chemical shift anisotropy (CSA) values of the active S(21)68 pinholin and inactive (SIRS)-I-21 pinholin indicated stronger head group interactions for the pinholin in its active form when compared to that of the inactive form supporting the model of a partially externalized peripheral transmembrane domain (TMD) of the active S(21)68 instead of complete externalized TMD1 as suggested by Ahammad et al. JPC B 2019. The H-2 quadrupolar splitting analysis showed a decrease in spectral width for both forms of the pinholin when compared to the empty bilayers at all temperatures. In this case the decrease in the spectral width of the inactive (SIRS)-I-21 form of the pinholin showed stronger interactions with the acyl chains of the bilayer. The presence of the inactive form's additional TMD within the membrane was supported by the loss of peak resolution observed in the H-2 NMR spectra.