中国科技论文在线

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2010年07月01日

陈忠周，丰艳梅，赵刚，赵玉芬

中国油脂，2000，25（5）：41～45，-0001，（）：

-1年11月30日

系统地介绍和评述了共轭亚油酸的化学、生理性质，来源，合成与转化，分离纯化及检测等领域近年来的进展。由于共轭亚油酸对实验动物具有抗突变、抗癌、抗动脉粥样硬化、减肥、缓和免疫反应副作用等许多优点，因此在药物和食品等研究领域中有很广阔的应用前景。

共轭亚油酸，生理性质，异构化，抗癌，分离纯化

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2010年07月01日

【期刊论文】催化剂对煤着火特性影响规律的计算机辅助研究(Ⅰ)碱金属、碱土金属盐对煤的催化着火规律①

陈忠周，武增华，许玲，胡鑫尧

计算机与应用化学，1996，13（4）：270～273，-0001，（）：

-1年11月30日

摘要

应用计算机高速采集煤在燃烧过程中的各瞬时温度，通过特殊软件的数据处理，可以直接得到表征煤着火特性的着火温度，并应用该种计算机辅助研究方法，研究碱金属、碱土金属盐类对煤的催化着火影响。研究表明：碱金属、碱土金属盐的催化活性，随对应的金属的第一电离能的减弱而递增。但带结晶水的碱土金属盐例外，其催化活性，明显优于该属不带结晶水的的盐。

煤，催化剂，着火特性，着火温度(，着火点、燃点)，

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2010年07月01日

【期刊论文】Structural Insights into Histone Demethylation by JMJD2 Family Members

陈忠周， Zhongzhou Chen，， Jianye Zang， Johnathan Whetstine， Xia Hong， Foteini Davrazou， Tatiana G. Kutateladze， Michael Simpson， Qilong Mao， Cheol-Ho Pan， Shaodong Dai， James Hagman， Kirk Hansen， Yang Shi， and Gongyi Zhang， *

，-0001，（）：

-1年11月30日

摘要

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2010年07月01日

【期刊论文】The use of crude lipase in deprotection of C-terminal protecting groups

陈忠周， Zhong-Zhou Chen， Yan-Mei Li∗， Xi Peng， Fu-Rong Huang， Yu-Fen Zhao

Journal of Molecular Catalysis B: Enzymatic 18(2002)243-249，-0001，（）：

-1年11月30日

摘要

A crude lipase, Newlase F, was used to remove C-terminal protecting groups from dipeptide esters. Hydrolysis of dipeptide n-heptyl esters with Newlase F was conducted in aqueous media containing acetonitrile. The optimum pH and temperature of lipase in Newlase F were 7.0 and 30 ◦C, respectively. Low level acetonitrile promoted the hydrolysis of dipeptide n-heptyl esters, while high level acetonitrile inhibited the hydrolysis. However, the protease activity in Newlase F was significantly inhibited by acetonitrile. Lipase in Newlase F worked better in a medium containing water-miscible organic solvents than in water-immiscible ones. N-terminal protecting groups were not affected by the protease in the crude enzyme. It was found that the protease in Newlase F did not hydrolyze amide bond with hydrophilic amino acids on either side under these conditions (pH 7.0, room temperature). Newlase F may consequently be used widely in the synthesis of peptide conjugates. The crude enzyme was immobilized on SBA-15 mesoporous molecular sieve. The lipase activity of immobilized preparation was more active on hydrolysis of C-terminal protecting groups and stable than the free enzyme. The immobilization also reduced the protease activity.

Newlase F， Dipeptide heptyl esters， Lipase， Protease

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2010年07月01日

【期刊论文】A common intermediate for prebiotic synthesis of proteins and nucleosides: a density functional theory (DFT) study on the formation of penta-coordinate phosphorus carboxylic-phosphoric mixed anhydride from N-phosphoryl amino acids

陈忠周， Bo Tan a， *， Matthew C. Lee b， Meng Cui c， Tong Liu c， Zhong-Zhou Chen a， Yan-Mei Li a， Yong Jua， Yu-Fen Zhao a， Kaixian Chen c， Hualiang Jiang c

Journal of Molecular Structure (Theochem) 672 (2004) 51-60，-0001，（）：

-1年11月30日

摘要

N-phosphoryl amino acids (PAA) are a unique chemical species with many chemical reactivities and properties, including the ability to self-assemble into oligopeptides. Because of their chemical characteristics, they have been proposed as the common origin for both nucleic acids and proteins. In this paper, we discussed six intramolecular mixed carboxylic-phosphoric anhydrides (IMCPAs) as possible intermediates for the prebiotic synthesis of biopolymers from PAA. We also investigated the role of water molecules in the formation of IMCPA using density functional theory B3LYP quantum mechanical calculations at the 6-31G** and 6-311 G** levels. Our results showed that the energy barrier of IMCPA formation was reduced from 19.5 kcal mol21 to 9.9 kcal mol21 when water participation and solvent effects were considered. Thus, the direct participation of one water molecule and the bulk solvent effects both play important roles in the formation of IMCPA.

Origins of life， N-phosphoryl amino acids， Intramolecular mixed carboxylic-phosphoric anhydride

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