Muller Ludovic, Jackson Shelley N, Woods Amina S
Structural Biology Unit, NIDA IRP, NIH, Baltimore, MD, USA.
Eur J Mass Spectrom (Chichester). 2019 Apr;25(2):212-218. doi: 10.1177/1469066718791793.
Electrostatic interactions are one of the main factors influencing biomolecular conformation. The formation of noncovalent complexes by electrostatic interactions is governed by certain amino acid residues and post-translational modifications. It has been demonstrated that adjacent arginine forms noncovalent complex with phosphate; however, histidine noncovalent complexes have rarely been investigated. In the present work, we compare the interaction between basic epitopes (NLRRITRVN, SHHGLHSTPD) and diverse acidic and aromatic-rich peptides using both MALDI and ESI Mass spectrometry. We show that adjacent histidines can also form stable noncovalent bonds and that those bonds are probably formed by a salt bridge between the phosphate or the acid residues and the histidines. However, noncovalent complexes with the arginine epitopes form more readily and are stronger than those with histidine-containing epitopes.
静电相互作用是影响生物分子构象的主要因素之一。通过静电相互作用形成非共价复合物受某些氨基酸残基和翻译后修饰的支配。已证明相邻的精氨酸与磷酸盐形成非共价复合物；然而，组氨酸非共价复合物很少被研究。在本工作中，我们使用基质辅助激光解吸电离（MALDI）和电喷雾电离（ESI）质谱法比较了碱性表位（NLRRITRVN、SHHGLHSTPD）与各种富含酸性和芳香族的肽之间的相互作用。我们表明相邻的组氨酸也能形成稳定的非共价键，并且这些键可能是由磷酸盐或酸性残基与组氨酸之间的盐桥形成的。然而，与精氨酸表位形成的非共价复合物比与含组氨酸表位形成的复合物更容易形成且更强。
