In this study, Gly→Ala was introduced into three chains of the heterotrimeric model (abc); seven mutants were subsequently constructed, and the local structure and global motion changes were analyzed. DSC results showed that the Tm value of the single point mutation was reduced by about 15°C, while the double and triple point mutations did not form triple helical structures. MD simulation trajectories were analyzed by ladder models; the results showed that the value of the step parameter changes near the mutation point, indicating an unfolding of the triple helix structure. An elastic function was introduced to quantify the degree of collagen structure change. It was found that the hydrogen bond energy was highly correlated with the structural deformation fraction ( $ R^2=0.76 $ ), indicating that the mutation not only destroyed the hydrogen bond force, but also resulted in changes in the bending and motion states of the molecule. This study, combined with calculations and experiments, helped quantify the effects of glycine mutation on the overall structure and movement pattern of collagen. Hence, the study provides a theoretical basis for clarifying the pathogenic mechanism of glycine mutation.
中国综合性科技类核心期刊(北大核心)
