The Synthesis and Characterization of Aromatic Hybrid Anderson-Evans POMs and their Serum Albumin Interactions: The Shift from Polar to Hydrophobic Interactions.
The Synthesis and Characterization of Aromatic Hybrid Anderson-Evans POMs and their Serum Albumin Interactions: The Shift from Polar to Hydrophobic Interactions.
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DOI：
10.1002/chem.201502458
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发表时间：
2015-12-01
期刊：
影响因子：
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通讯作者：
Rompel A
中科院分区：
文献类型：
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作者：
Al-Sayed E;Blazevic A;Roller A;Rompel A
采用预官能化方法合成了四种以Fe ~（3+）或Mn ~（3+）为中心杂原子的芳香族杂化安德森钼酸盐，并通过单晶X射线衍射、红外光谱、电喷雾质谱、核磁共振氢谱和元素分析对其结构进行了表征。 结构分析表明，形成了（TBA）3[FeMo 6 O 18 {（OCH 2）3CNHCOC 6 H5}2]<$3.5 ACN（TBA-FeMo 6-bzn; TBA=四丁基铵，ACN=乙腈，bzn= TRIS-苯甲酸烷醇酰胺，TRIS-R=（HOCH 2）3C-R）），（TBA）3[FeMo 6 O 18 {（OCH 2）3CNHCOC 8H 7}2]= 2.5 ACN（TBA-FeMo 6-cin; cin= Tris-肉桂酸烷醇酰胺），（TBA）3[MnMo 6 O 18 {（OCH 2）3CNHCOC 6 H5}2]<$3.5 ACN（TBA-MnMo 6-bzn），和（TBA）3[MnMo 6 O 18 {（OCH 2）3CNHCOC 8 H7}2]<$2.5 ACN（TBA-MnMo 6-cin）。为了使这四种化合物可应用于生物系统，进行离子交换，得到水溶性（高达80 mM）钠盐Na 3 [FeMo 6 O 18 {（OCH 2）3CNHCOC 6 H5}2]（Na-FeMo 6-bzn）、Na 3 [FeMo 6 O 18 {（OCH 2）3CNHCOC 8H 7}2]（Na-FeMo 6-cin）、Na 3 [MnMo 6 O 18 {（OCH 2）3CNHCOC 6 H5}2]（Na-MnMo 6-bzn）和Na 3 [MnMo 6 O 18 {（OCH 2）3CNHCOC 8H 7}2]（Na-MnMo 6-cin）。 通过在4至9的pH范围内应用ESI-MS检查钠盐的水解稳定性。十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）显示，人和牛血清白蛋白（HSA和BSA）在含有高达100当量钠盐的溶液中在20 °C下超过4天保持完整。 在pH 5.5和7.4条件下，用色氨酸荧光猝灭法研究了钠盐与人血清白蛋白（HSA）和牛血清白蛋白（BSA）的相互作用。 通过Stern-Volmer分析提取了猝灭常数，这表明在所有样品中形成1：1的POM-蛋白质复合物。有人建议，芳族杂合POM的方法亚结构域IIA的HSA，并表现出疏水相互作用，其疏水性的尾巴，而安德森核心是通过静电相互作用稳定的极性氨基酸侧链，例如，亚结构域IB。
Four aromatic hybrid Anderson polyoxomolybdates with Fe3+ or Mn3+ as the central heteroatom have been synthesized by using a pre-functionalization protocol and characterized by using single-crystal X-ray diffraction, FTIR, ESI-MS, 1H NMR spectroscopy, and elemental analysis. Structural analysis revealed the formation of (TBA)3[FeMo6O18{(OCH2)3CNHCOC6H5}2]⋅3.5 ACN (TBA-FeMo6-bzn; TBA=tetrabutylammonium, ACN=acetonitrile, bzn=TRIS-benzoic acid alkanolamide, TRIS–R=(HOCH2)3C–R)), (TBA)3[FeMo6O18{(OCH2)3CNHCOC8H7}2]⋅2.5 ACN (TBA-FeMo6-cin; cin=TRIS-cinnamic acid alkanolamide), (TBA)3[MnMo6O18{(OCH2)3CNHCOC6H5}2]⋅3.5 ACN (TBA-MnMo6-bzn), and (TBA)3[MnMo6O18{(OCH2)3CNHCOC8H7}2]⋅2.5 ACN (TBA-MnMo6-cin). To make these four compounds applicable in biological systems, an ion exchange was performed that gave the water-soluble (up to 80 mm) sodium salts Na3[FeMo6O18{(OCH2)3CNHCOC6H5}2] (Na-FeMo6-bzn), Na3[FeMo6O18{(OCH2)3CNHCOC8H7}2] (Na-FeMo6-cin), Na3[MnMo6O18{(OCH2)3CNHCOC6H5}2] (Na-MnMo6-bzn), and Na3[MnMo6O18{(OCH2)3CNHCOC8H7}2] (Na-MnMo6-cin). The hydrolytic stability of the sodium salts was examined by applying ESI-MS in the pH range of 4 to 9. Sodium dodecylsulfate–polyacrylamide gel electrophoresis (SDS-PAGE) showed that human and bovine serum albumin (HSA and BSA) remain intact in solutions that contain up to 100 equivalents of the sodium salts over more than 4 d at 20 °C. Tryptophan (Trp) fluorescence quenching was applied to study the interactions between the sodium salts and HSA and BSA at pH 5.5 and 7.4. The quenching constants were extracted by using Stern–Volmer analysis, which suggested the formation of a 1:1 POM–protein complex in all samples. It is suggested that the aromatic hybrid POM approaches subdomain IIA of HSA and exhibits hydrophobic interactions with its hydrophobic tails, whereas the Anderson core is stabilized through electrostatic interactions with polar amino acid side chains from, for example, subdomain IB.