1. Cation-amino acid interactions: Implications for protein destabilization
- Author
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Guangzhao Zhang, Jiantao Chen, Xiangjun Gong, and Yingkang Dai
- Subjects
inorganic chemicals ,0301 basic medicine ,Guanidinium chloride ,Stereochemistry ,Proton Magnetic Resonance Spectroscopy ,Biophysics ,chemistry.chemical_element ,Biochemistry ,Ammonium Chloride ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Cations ,Side chain ,Amino Acids ,Molecular Biology ,Guanidine ,chemistry.chemical_classification ,Protein Stability ,Hydrogen bond ,Cell Biology ,Sulfur ,Amino acid ,Solutions ,030104 developmental biology ,chemistry ,Protein destabilization ,030220 oncology & carcinogenesis ,Protein stabilization ,Hydrogen ,Cysteine - Abstract
The mechanism for protein stabilization or destabilization has long been an open quest. In the present study, we have studied the interactions between amino acids and guanidinium (Gdm+)/ammonium (NH4+) ions by using low field nuclear magnetic resonance (LF-NMR), where Gdm+ and NH4+ are denaturant and stabilizer for proteins, respectively. It shows that Gdm+ favors to bind to the thiol group or the hydroxyl group on the side chain but weakly interacts with the α-carboxyl group. In contrast, NH4+ prefers to bind to the α-carboxyl group but slightly interacts with the thiol group or the hydroxyl group on the side chain of amino acids. 1HNMR reveals the hydrogen bonding between NH4+ and the α-carboxyl group, which is not involved in the interactions between Gdm+ and cysteine. Our study demonstrates that the strong interactions between the denaturant and the sulfur atom or the disulfide bond promote the direct binding of the denaturant toward proteins, leading to the destabilization.
- Published
- 2021