Su Zhaoqian, Mahmoudinobar Farbod, Dias Cristiano L
Physics Department, New Jersey Institute of Technology, Newark, 07102-1982 New Jersey, USA.
Phys Rev Lett. 2017 Sep 8;119(10):108102. doi: 10.1103/PhysRevLett.119.108102.
To provide insights into the stabilizing mechanisms of trimethylamine-N-oxide (TMAO) on protein structures, we perform all-atom molecular dynamics simulations of peptides and the Trp-cage miniprotein. The effects of TMAO on the backbone and charged residues of peptides are found to stabilize compact conformations, whereas effects of TMAO on nonpolar residues lead to peptide swelling. This suggests competing mechanisms of TMAO on proteins, which accounts for hydrophobic swelling, backbone collapse, and stabilization of charge-charge interactions. These mechanisms are observed in Trp cage.
为深入了解氧化三甲胺（TMAO）对蛋白质结构的稳定机制，我们对肽段和色氨酸笼状微蛋白进行了全原子分子动力学模拟。研究发现，TMAO对肽段主链和带电荷残基的作用可稳定紧凑构象，而TMAO对非极性残基的作用则导致肽段膨胀。这表明TMAO对蛋白质存在相互竞争的机制，这可以解释疏水膨胀、主链塌陷以及电荷-电荷相互作用的稳定。在色氨酸笼状微蛋白中也观察到了这些机制。
