摘要
首次采用AM1半经验量子化学计算方法研究了10种D型和L型氨基酸的电子结构。使用Gaussian94软件包对所有结构进行了全优化和频率分析,得到了一系列的量子化学参数。研究结果表明,D型氨基酸的生成热、偶极矩、最低未占轨道能量、最高已占轨道能量及前线轨道能隙值与其L型相比明显不同。D型氨基酸的生成热、偶极矩、最低未占轨道能量及前线轨道能隙值比其对应的L型氨基酸的增加可能增强了D型氨基酸与甜味蛋白质接受体的相互作用,从而表现出D型氨基酸比其相对应L型氨基酸甜味强的特性。
The electronic structures of 10 kinds of D-form and L-form amino acids have been investigated by employing AM 1 semiempirical quantum chemical method firstly. Full optimization and frequency analysis of all structures have been performed using Gaussian94 software-package and a series of quantum chemical parameters have been obtained. The results show that the heat of formation （HF）, dipole moment, energy of lowest unoccupied molecular orbital （ELUMO）, energy of highest occupied molecular orbital （EHOMO） and energy gap of frontier molecular orbitals （ΔE=ELUMO-EHOMO） of D-form amino acids are significantly different from those of corresponding L-form amino acids. The increased sweetness of D-form amino acids may be due to the increase of HF, dipole moment, ELUMO and AE of D-form amino acids in contrast to that of corresponding L-form amino acids. The enhancing of quantum chemical parameters may be favorable to the strong interaction between D-form amino acids and the sweetness protein receptor.
出处
《化学世界》
CAS
CSCD
北大核心
2006年第2期74-77,共4页
Chemical World
关键词
氨基酸
甜味
AM1半经验方法
量子化学参数
amino acid
sweetness
AM1 semiempirical method
quantum chemical parameters
