Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang, 621010, China.
State Key Laboratory of Environment-Friendly Energy Materials, Southwest University of Science and Technology, Mianyang, 621010, China.
Interdiscip Sci. 2021 Mar;13(1):140-146. doi: 10.1007/s12539-020-00402-7. Epub 2020 Nov 13.
A workable approach named xTB-sTDDFT was selected to investigate the excited-state spectra of oxytocin (135 atoms), GHRP-6 (120 atoms) and insulin (793 atoms). Three different Hartree-Fock components functionals (wB97XD3: 51%, LC-BLYP: 53%, wB97X: 57%) were used to calculate the excitation spectra, and the results calculated by wB97XD3 functional well agree with the experiments. It's a deep impression that computed time cost reduced by more than 80%. For polypeptide (oxytocin and GHRP-6), both UV and fluorescence spectra were obtained, and the errors between the calculated and experimental values approximately were 20 nm. For Insulin, the errors are within 15 nm. UV spectrum peak is λ = 262 nm (λ = 277 nm, Δλ = 15 nm), and fluorescence spectrum peak is λ = 294 nm (λ = 304 nm, Δλ = 10 nm). In summary, a suitable theoretical model is established to ultra-fast calculate the electronic excitation spectra of large systems, such as proteins and biomacromolecules, with good calculation accuracy, fast calculation speed and low cost.
选择了一种可行的方法 xTB-sTDDFT 来研究催产素（135 个原子）、GHRP-6（120 个原子）和胰岛素（793 个原子）的激发态光谱。使用了三种不同的 Hartree-Fock 分量泛函（wB97XD3：51%、LC-BLYP：53%、wB97X：57%）来计算激发光谱，wB97XD3 功能计算的结果与实验很好地吻合。令人印象深刻的是，计算时间成本降低了 80%以上。对于多肽（催产素和 GHRP-6），同时获得了紫外和荧光光谱，计算值与实验值之间的误差约为 20nm。对于胰岛素，误差在 15nm 以内。紫外光谱峰为 λ=262nm（λ=277nm，Δλ=15nm），荧光光谱峰为 λ=294nm（λ=304nm，Δλ=10nm）。总之，建立了一个合适的理论模型，能够快速准确地计算蛋白质和生物大分子等大型系统的电子激发光谱，具有计算速度快、计算成本低、计算精度高等优点。
