TY - JOUR
T1 - Conformational flexibility of phycocyanobilin
T2 - Monte-Carlo and DFT study
AU - Tu, Ping hui
AU - Yao, Yu heng
AU - Li, Yin li
AU - Liu, Bo
PY - 2009/1/30
Y1 - 2009/1/30
N2 - A scan of the potential-energy surface (PES) for phycocyanobilin has been performed by Monte-Carlo Multiple Minimum (MCMM) searching method using the force field of MMFFs. The resulting most stable/populated structures are then reoptimized with ab initio methods and density functional theory (DFT) using HF/6-31G and B3LYP/6-31G levels of theory, and all possible conformers of phycocyanobilin are investigated with these methods. Results indicate that the most stable structure is all-syn, all-Z conformation. Other local minima are also obtained, such as ZZZass, EZZass and ZZZssa, which are stabilized by intramolecular hydrogen bonds and favorable geometric structures minimizing steric interactions.
AB - A scan of the potential-energy surface (PES) for phycocyanobilin has been performed by Monte-Carlo Multiple Minimum (MCMM) searching method using the force field of MMFFs. The resulting most stable/populated structures are then reoptimized with ab initio methods and density functional theory (DFT) using HF/6-31G and B3LYP/6-31G levels of theory, and all possible conformers of phycocyanobilin are investigated with these methods. Results indicate that the most stable structure is all-syn, all-Z conformation. Other local minima are also obtained, such as ZZZass, EZZass and ZZZssa, which are stabilized by intramolecular hydrogen bonds and favorable geometric structures minimizing steric interactions.
KW - DFT
KW - Monte-Carlo
KW - Open-chain tetrapyrroles
KW - Phycocyanobilin
UR - http://www.scopus.com/inward/record.url?scp=57449102029&partnerID=8YFLogxK
U2 - 10.1016/j.theochem.2008.09.034
DO - 10.1016/j.theochem.2008.09.034
M3 - Article
AN - SCOPUS:57449102029
SN - 0166-1280
VL - 894
SP - 9
EP - 13
JO - Journal of Molecular Structure: THEOCHEM
JF - Journal of Molecular Structure: THEOCHEM
IS - 1-3
ER -