As the theoretical foundation of organic chemistry, physical organicchemistry mainly deals with the relationship between structure, medium and the chemical and physicalproperties of organic molecules. Over the past 20...As the theoretical foundation of organic chemistry, physical organicchemistry mainly deals with the relationship between structure, medium and the chemical and physicalproperties of organic molecules. Over the past 20 years or so, a research group under theleadership of Prof. Jiang Xikui of the CAS Shanghai Institute of Organic Chemistry, with thelong-term support from the National Natural Science Foundation of China (NSFC), has carried outstudies at two important frontiers of this field, i.e. aggregation and self-coiling of organicmolecules, and the successful establishment and application of the sigma_(JJ) scale ofspin-delocalization substituent constants. The researchers made significant contributions in theirstudies, which concerns with both the structural effect and medium effect, two of the importantaspects of physical organic chemistry, and received the first-grade prize of the National Awards forNatural Sciences in 2002.展开更多
The rebinding kinetics of an amino acid ligand to ferrous microperoxidase-11 (MP11) after photolysis of aggregated ferrous MP11 was measured in aqueous solution with femtosecond transient visible absorption spectrosco...The rebinding kinetics of an amino acid ligand to ferrous microperoxidase-11 (MP11) after photolysis of aggregated ferrous MP11 was measured in aqueous solution with femtosecond transient visible absorption spectroscopy. The kinetics of CO rebinding to ferrous MP11 after photolysis of MP11CO was also measured in aqueous solution with femtosecond transient visible absorption spectroscopy. From these measurements, we found that either Val-11 or Lys-13 rebinds to ferrous MP11 exponentially with an 8 picosecond time constant in aggregated ferrous MP11 solution and that CO rebinds to ferrous MP11 nonexponentially with subnanosecond time scale in MP11CO solution. The kinetics of both the amino acid and CO rebinding to ferrous MP11 in MP11 system mimics that in carbon monoxide oxidation activator protein (CooA) or carboxymethyl cytochrome c (CmCytC) system. We also measured the kinetics of CO rebinding to ferrous MP11 in aqueous solution at different MP11CO concentrations and found that MP11CO concentration has an obvious effect on the kinetics of CO rebinding to ferrous MP11, where both the germinate yield and rate of CO rebinding to ferrous MP11 increase with the increase of MP11CO concentration. These findings suggested that the picosecond amino acid ligand rebinding process could disturb the proximal heme-ligand structure that possibly leads to the subnanosecond CO rebinding kinetics in MP11CO, CooACO and CmCytCCO systems.展开更多
文摘As the theoretical foundation of organic chemistry, physical organicchemistry mainly deals with the relationship between structure, medium and the chemical and physicalproperties of organic molecules. Over the past 20 years or so, a research group under theleadership of Prof. Jiang Xikui of the CAS Shanghai Institute of Organic Chemistry, with thelong-term support from the National Natural Science Foundation of China (NSFC), has carried outstudies at two important frontiers of this field, i.e. aggregation and self-coiling of organicmolecules, and the successful establishment and application of the sigma_(JJ) scale ofspin-delocalization substituent constants. The researchers made significant contributions in theirstudies, which concerns with both the structural effect and medium effect, two of the importantaspects of physical organic chemistry, and received the first-grade prize of the National Awards forNatural Sciences in 2002.
基金financially supported by the National Natural Science Foundation of China (20603047, 20733001)the Fundamental Research Funds for the Central Universitiesthe Research Funds of Renmin University of China (10XNJ047)
文摘The rebinding kinetics of an amino acid ligand to ferrous microperoxidase-11 (MP11) after photolysis of aggregated ferrous MP11 was measured in aqueous solution with femtosecond transient visible absorption spectroscopy. The kinetics of CO rebinding to ferrous MP11 after photolysis of MP11CO was also measured in aqueous solution with femtosecond transient visible absorption spectroscopy. From these measurements, we found that either Val-11 or Lys-13 rebinds to ferrous MP11 exponentially with an 8 picosecond time constant in aggregated ferrous MP11 solution and that CO rebinds to ferrous MP11 nonexponentially with subnanosecond time scale in MP11CO solution. The kinetics of both the amino acid and CO rebinding to ferrous MP11 in MP11 system mimics that in carbon monoxide oxidation activator protein (CooA) or carboxymethyl cytochrome c (CmCytC) system. We also measured the kinetics of CO rebinding to ferrous MP11 in aqueous solution at different MP11CO concentrations and found that MP11CO concentration has an obvious effect on the kinetics of CO rebinding to ferrous MP11, where both the germinate yield and rate of CO rebinding to ferrous MP11 increase with the increase of MP11CO concentration. These findings suggested that the picosecond amino acid ligand rebinding process could disturb the proximal heme-ligand structure that possibly leads to the subnanosecond CO rebinding kinetics in MP11CO, CooACO and CmCytCCO systems.
