The synthesis of(S)-1-phenyl-1,2-ethanediol was studied in this article.Firstly,1,2-dibromo-1-phenylethane was synthesized with styrene and bromine as starting agents.The effects of some factors,including raw material...The synthesis of(S)-1-phenyl-1,2-ethanediol was studied in this article.Firstly,1,2-dibromo-1-phenylethane was synthesized with styrene and bromine as starting agents.The effects of some factors,including raw materials’ molar ratio,reaction time and solvents,on the yield of 1,2-dibromo-1-phenylethane were examined.Secondly,1-phenyl-1,2-ethanediol was obtained by use of hydrolysis of 1,2-dibromo-1-phenylethane in alkaline medium.The influence of reaction time and medium on the yield of 1-phenyl-1,2-ethanediol was also examined.Under the optimized conditions,the yield of 1,2-dibromo-1-phenylethane was 90.1% while the yield of 1-phenyl-1,2-ethanediol was 78.5%.Finally,(S)-1-phenyl-1,2-ethanediol was received by deracemization of 1-phenyl-1,2-ethanediol employing Candida parapsilosis.The enantiomeric excess of(S)-1-phenyl-1,2-ethanediol was 99% and the conversion was 88%.展开更多
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
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
文摘The synthesis of(S)-1-phenyl-1,2-ethanediol was studied in this article.Firstly,1,2-dibromo-1-phenylethane was synthesized with styrene and bromine as starting agents.The effects of some factors,including raw materials’ molar ratio,reaction time and solvents,on the yield of 1,2-dibromo-1-phenylethane were examined.Secondly,1-phenyl-1,2-ethanediol was obtained by use of hydrolysis of 1,2-dibromo-1-phenylethane in alkaline medium.The influence of reaction time and medium on the yield of 1-phenyl-1,2-ethanediol was also examined.Under the optimized conditions,the yield of 1,2-dibromo-1-phenylethane was 90.1% while the yield of 1-phenyl-1,2-ethanediol was 78.5%.Finally,(S)-1-phenyl-1,2-ethanediol was received by deracemization of 1-phenyl-1,2-ethanediol employing Candida parapsilosis.The enantiomeric excess of(S)-1-phenyl-1,2-ethanediol was 99% and the conversion was 88%.
基金This study was supported by the National Basic Research Program of China(No.2003CB716008)the Program for Changjiang Scholars and Innovative Research Team in University(PCSIRT,IRT0532).
文摘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.
基金This work was supported by the National Natural Science Foundation of China(Grant No.20376031)the National Key Basic Research and Development Program of China(973 Program)(Grant No.2003CB716008)+1 种基金the Program for New Century Excellent Talents in University,Ministry of Education,China(Grant No.NCET-04-0498)the Program for Changjiang Scholars and Innovative Research Team in University(Grant No.PCSIRT,IRT0532).
文摘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.
