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Screening for microbe displaying diastereoselective ketoreductase activity towards t-butyl 6-cyano-(5R)-hydroxyl-3-oxohexanoate

具有差向选择性还原(R)-6-氰基-5-羟基-3-羰基己酸叔丁酯活性的微生物菌株筛选和鉴定



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ChineseJournalofBioprocessEngineering
Vol.11No.1
Jan.2013
doi:10.3969/j.issn.1672-3678.2013.01.010
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:1672-3678(2013)01-0054-06
Screeningformicrobedisplayingdiastereoselectiveketoreductaseactivity
towardstbutyl6cyano(5R)hydroxyl3oxohexanoate
SHENGJunzhen,WANGYajun,LUOXi,ZHENGYuguo
(EngineeringResearchCenterofBioconversionandBiopurificationoftheMinistryofEducation,
InstituteofBioengineering,ZhejiangUniversityofTechnology,Hangzhou310014,China)
Abstract:AstrainZJB09225displayingdiastereoselectiveketoreductaseactivitytowardstbutyl6cyano
(5R)hydroxyl3oxohexanoatewasisolatedandidentifiedasPichiacaribbicbyphenotypic,biochemical
characteristicsandalignmentanalysisof18SrDNAsequence.Resultsrevealedthatafter32hculture
undertheoptimizedfermentationconditions,thevolumetricactivityandthebiomassdensityofP.caribbic
ZJB09225were72U/Land88g/L,respectively.P.caribbicZJB09225wasmostactivetotbutyl6
cyano(5R)hydroxyl3oxohexanoateat35℃ andpH75.Inaddition,500g/Ltbutyl6cyano(5R)
hydroxyl3oxohexanoate was diastereoselectively reduced to tbutyl 6cyano(3R, 5R)
dihydroxyhexanoatebyP.caribbicZJB09225for3h,inayieldof34% withd.e.valueover995%.
Keywords:ketoreductase;Pichiacaribbic;atorvastatin;tbutyl6cyano(3R,5R)dihydroxyhexanoate
  
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Fig.1 Enzymaticconversionoftbutyl6cyano(5R)hydroxy3oxohexanoate
totbutyl6cyano(3R,5R)dihydroxyhexanoatebyketoreductase.
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ketoreductaseactivitytowards
tbutyl6cyano(5R)hydroxyl3
oxohexanoateusingcolorimetric
reaction
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