Linked Life Data

21515382

Source:http://linkedlifedata.com/resource/pubmed/id/21515382

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2011-7-11
pubmed:abstractText
A putative epoxide hydrolase-encoding gene was identified from the genome sequence of Cupriavidus metallidurans CH34. The gene was cloned and overexpressed in Escherichia coli with His(6)-tag at its N-terminus. The epoxide hydrolase (CMEH) was purified to near homogeneity and was found to be a homodimer, with subunit molecular weight of 36 kDa. The CMEH had broad substrate specificity as it could hydrolyze 13 epoxides, out of 15 substrates tested. CMEH had high specific activity with 1,2-epoxyoctane, 1,2-epoxyhexane, styrene oxide (SO) and was also found to be active with meso-epoxides. The enzyme had optimum pH and temperature of 7.5 and 37°C respectively, with racemic SO. Biotransformation of 80 mM SO with recombinant whole E. coli cells expressing CMEH led to 56% ee(P) of (R)-diol with 77.23% conversion in 30 min. The enzyme could hydrolyze (R)-SO, ?2-fold faster than (S)-SO, though it accepted both (R)- and (S)-SO with similar affinity as K(m)(R) and K(m)(S) of CMEH were 2.05±0.42 and 2.11±0.16 mM, respectively. However, the k(cat)(R) and k(cat)(S) for the two enantiomers of SO were 4.80 and 3.34 s(-1), respectively. The wide substrate spectrum exhibited by CMEH combined with the fast conversion rate makes it a robust biocatalyst for industrial use. Regioselectivity studies with enantiopure (R)- and (S)-SO revealed that with slightly altered regioselectivity, CMEH has a high potential to synthesize an enantiopure (R)-PED, through an enantioconvergent hydrolytic process.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1096-0279
pubmed:author
pubmed:copyrightInfo
Copyright © 2011 Elsevier Inc. All rights reserved.
pubmed:issnType
Electronic
pubmed:volume
79
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
49-59
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Cloning and characterization of an epoxide hydrolase from Cupriavidus metallidurans-CH34.
pubmed:affiliation
Department of Biochemistry, Panjab University, Chandigarh, India.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't