水液相下羟基负离子催化两性赖氨酸分子手性反转的理论研究  

Theoretical study on the chiral flip of amphoteric lysine molecule catalyzed by hydroxyl anion in water-liquid phase environment

作　　者：李斌 刘芳[2] 张雪娇 王涵[3] 范艳杰 姜春旭 王佐成 LI Bin;LIU Fang;ZHANG Xuejiao;WANG Han;FAN Yanjie;JIANG Chunxu;WANG Zuocheng(College of Communication,Baicheng Normal University,Baicheng 137000,China;Theoretical Computing Center,Baicheng Normal University,Baicheng 137000,China;Physics Group of the Luxiang School,Dongfeng County,Siping 136000,China)

机构地区：[1]白城师范学院传媒学院,吉林白城137000 [2]白城师范学院理论计算中心,吉林白城137000 [3]东丰县鹿乡中学物理组,吉林四平136000

出　　处：《中山大学学报（自然科学版）（中英文）》2023年第2期73-82,共10页Acta Scientiarum Naturalium Universitatis Sunyatseni

基　　金：吉林省白城市科技发展计划攻关项目(JBKH20220001KJ);吉林省科技厅自然科学基金(20160101308JC)。

摘　　要：采用密度泛函理论的M06-2X和MN15方法,结合自洽反应场理论的SMD模型方法,研究了水液相下羟基负离子催化两性赖氨酸分子的手性反转。反应过程研究发现:经过羟基负离子水分子簇抽取α-H质子和碳负离子的α-C抽取水分子簇的H质子过程,赖氨酸分子实现手性反转。势能面计算表明:羟基负离子水分子簇与α-H和羰基O氢键作用,赖氨酸分子实现手性反转的决速步能垒为51.1~59.9 kJ/mol;羟基负离子水分子簇与α-H和氨基N氢键作用,赖氨酸分子实现手性反转的决速步能垒为52.8~58.0 kJ/mol,均远低于水液相下两性赖氨酸分子手性反转的能垒110.0 kJ/mol。结果表明,水液相下羟基负离子对赖氨酸的手性反转有催化作用,碱性环境不利于健康。Using M06-2X and MN15 methods of density functional theory,combining with SMD model method of self consistent reaction field theory,the chiral flip of amphoteric lysine molecule catalyzed by hydroxyl anion in water-liquid phase environment was investigated.The study of reaction process shows that through the process of extractingα-H proton from hydroxyl anion water clusters and extracting H proton of water clusters from carbanionα-C,lysine molecules could achieve chiral flip.The potential energy surface shows that the energy barrier of the lysine molecules chiral flip rate-deter‐mining step is between 51.1 kJ/mol and 59.9 kJ/mol when the clusters of hydroxyl anion water molecules interact withα-H and carbonyl O hydrogen bonds;the energy barrier of the lysine molecules chiral flip rate-determining step is between 52.8 and 58.0 kJ/mol when the clusters of hydroxyl anion water molecules interact withα-H and amino group N hydrogen bonds,they are much lower than the energy barrier 110 kJ/mol of chiral flip of amphoteric lysine molecule in water-liquid phase environment.The results show that the hydroxyl anions play a catalytic role on the chiral flip of lysine molecules in water-liquid phase environment,alkaline environment is insalubrious.

关 键 词：赖氨酸 手性反转 密度泛函理论 自洽反应场理论 过渡态 能垒 

分 类 号：O641.12[理学—物理化学]