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磺化β-环糊精毛细管电泳法分析对氯苯乙二醇对映体的光学纯度 被引量:2
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作者 赵燕 杨兴斌 +2 位作者 孙晓莉 柳文敏 张生勇 《分析测试学报》 CAS CSCD 北大核心 2006年第3期50-52,共3页
为分析不对称二羟化产物对氯苯乙二醇对映体样品的光学纯度,建立了对氯苯乙二醇对映体的毛细管电泳(CE)手性分离方法。以磺化β-环糊精(S--βCD)为手性选择剂,通过对S--βCD浓度、背景电解质pH值、操作电压等分离影响因素的研究,优化了... 为分析不对称二羟化产物对氯苯乙二醇对映体样品的光学纯度,建立了对氯苯乙二醇对映体的毛细管电泳(CE)手性分离方法。以磺化β-环糊精(S--βCD)为手性选择剂,通过对S--βCD浓度、背景电解质pH值、操作电压等分离影响因素的研究,优化了分离条件,成功地对对氯苯乙二醇对映体样品进行了手性拆分;同时,也对该对映体样品进行了光学纯度检查,并与HPLC测定结果作比较。结果表明,3批样品中对映体过量(e.e.)测定值与HPLC法结果相一致。该CE方法简单、准确,可用于该对氯苯乙二醇中性化合物的手性拆分和e.e.值的测定。 展开更多
关键词 对氯苯乙二醇 磺化β-环糊精 手性分离 光学纯度 毛细管电泳
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Cloning and expression of the gene encoding(R)-specific carbonyl reductase from Candida parapsilosis CCTCC M203011
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作者 Na XU Haiyan WANG +2 位作者 Yao NIE Yan XU Rong XIAO 《Frontiers in Biology》 CSCD 2008年第1期19-25,共7页
The gene which encodes(R)-specific carbonyl reductase(rCR)from Candida parapsilosis CCTCC M203011 was cloned,sequenced and compared with genes from the GenBank.The results indicated that rCR gene was 1011 bp,encoding ... The gene which encodes(R)-specific carbonyl reductase(rCR)from Candida parapsilosis CCTCC M203011 was cloned,sequenced and compared with genes from the GenBank.The results indicated that rCR gene was 1011 bp,encoding a protein of 336 amino acids with a molecular weight of 35.9 kDa,and its nucleotide sequence showed 99%similarity to those of other members of the alcohol dehydrogenase superfamily.The rCR gene could express in recombinant strain Escherichia coli JM109,and the expression plasmid could produce(R)-1-pheny-1,2-ethanediol(100%e.e.,80.14%yield)from b-hydroxyacetophenone without any additive to regenerate NAD+from NADH. 展开更多
关键词 carbonyl reductase EXPRESSION asymmetric reduction (R)-1-phenyl-1 2-ethanediol
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定点突变提高菜豆环氧水解酶的对映选择性
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作者 宗迅成 胡蝶 +2 位作者 阚婷婷 王婷婷 邬敏辰 《化工学报》 EI CAS CSCD 北大核心 2018年第10期4335-4341,共7页
为了提高菜豆环氧水解酶(PvEH1)催化对氯环氧苯乙烷(pCSO)的对映选择性,利用定点突变构建了PvEH1^(W102L)、PvEH1^(P137K)及PvEH1^(I151V)三种突变体,分别研究了突变体全细胞动力学拆分rac-pCSO的催化特性,优化了PvEH1W102L动力学拆分ra... 为了提高菜豆环氧水解酶(PvEH1)催化对氯环氧苯乙烷(pCSO)的对映选择性,利用定点突变构建了PvEH1^(W102L)、PvEH1^(P137K)及PvEH1^(I151V)三种突变体,分别研究了突变体全细胞动力学拆分rac-pCSO的催化特性,优化了PvEH1W102L动力学拆分rac-pCSO的初始底物浓度及反应时间,通过分子模拟分析了PvEH1^(W102L)对映选择性提高的机理。结果表明,最优突变体PvEH1^(W102L)的E值为25.5,相对酶活为212.6%,分别是PvEH1的11.6倍与2.1倍;PvEH1^(W102L)动力学拆分150 mmol·L^(-1) rac-pCSO,反应4 h后,可获得(R)-pCSO(产率为45.62%,ees为96.30%)和(R)-对氯苯基乙二醇(产率为50.91%,eep为90.26%)。分子模拟结果分析表明,PvEH1的102位色氨酸(W)突变为亮氨酸(L)降低了酶与(R)-pCSO的结合能力,从而提高了PvEH1^(W102L)对pCSO的对映选择性。 展开更多
关键词 生物催化 定点突变 环氧水解酶 对氯环氧苯乙烷 对氯苯基乙二醇 分子模拟
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Purification and characterization of a novel carbonyl reductase with high stereo-selectivity
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作者 YANG Ming XU Yan +1 位作者 MU Xiaoqing XIAO Rong 《Frontiers of Chemical Science and Engineering》 SCIE EI CSCD 2007年第4期404-410,共7页
A novel NADPH-dependent carbonyl reductase was separated from Candida parapsilosis CCTCC 203011.The enzyme gave a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE),which was purified t... A novel NADPH-dependent carbonyl reductase was separated from Candida parapsilosis CCTCC 203011.The enzyme gave a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE),which was purified through ammonium sulfate,Diethylamino Ethanol(DEAE)sepharose Fast flow(FF),phenyl-sepharose FF and blue sepharose FF chromato graphy from cell-free extract.The molecular mass of the enzyme was about 30 kDa.The optimum pH and temperature for reduction were 4.5℃ and 35℃,respectively.The Cu2+had strong restrictive effect on enzyme activity.In addition,the carbonyl reductase was an enzyme with high substrate specificity and stereo-selectivity,and showed high asymmetric reduction activity towards a-hydroxyacetophenone and ethyl 4-chloro acetoacetate.For the asymmetric reduction of a-hydroxyacetophenone and ethyl 4-chloro acetoacetate,(S)-1-phenyl-1,2-ethanediol and(R)-ethyl 4-chloro-3-hydroxybutanoate were produced by the purified enzyme,with the 100% and 94.3%e.e.value,respec-tively.Therefore,the enzyme could be one of the effective biocatalysts for asymmetric synthesis of chiral alcohols.The amino acid sequences of one peptide from the purified enzyme were analyzed by LC-MASS-MASS,and the car-bonyl reductase showed some identity to the hypothetical protein CaO19.10414 reported. 展开更多
关键词 BIOCATALYSIS carbonyl reductase purification (S)-1-phenyl-1 2-ethanediol (R)-ethyl 4-chloro-3-hydroxybutanoate
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