Stereoselectivities of microbial epoxide hydrolases

Orru, Romano V. A.; Faber, Kurt

doi:10.1016/s1367-5931(99)80004-0

Cited by 63 publications

(25 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The distinct preference towards hydrolysis of the (R)-epoxide was in correlation with previous studies on fungal EHs Orru and Faber, 1999) and yielded (S )-(2,3-epoxypropyl)benzene with an enantiomeric excess of substrate (ee s ) of 97% and a yield of 55%. The activity, selectivity and yield of the recombinant organism was far better than data obtained from various wild-type yeasts studied by Lotter (2000) for the hydrolytic kinetic resolution of (2,3-epoxypropyl)benzene.…”

Section: Construction Of a Constitutive Y Lipolytica Integrative Vecsupporting

confidence: 68%

“…3.3.2.3) have the ability to catalyse the enantioselective hydrolysis of epoxides to the corresponding diols. EHs are found in a wide variety of organisms, including plants, bacteria, fungi, mammals and yeasts (Orru and Faber, 1999). The hydrolysis of an epoxide by these structurally and mechanistically similar enzymes proceeds via an enzyme-ester-substrate intermediate (Lacourciere and Armstrong, 1993), resulting in the formation of the corresponding vicinal trans-diol with either retention or inversion of configuration, depending on the regioselectivity of the enzyme and the substitutional pattern of the carbon atom involved (Orru and Faber, 1999) (Figure 1).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Cloning of an epoxide hydrolase‐encoding gene from Rhodotorula mucilaginosa and functional expression in Yarrowia lipolytica

Labuschagne

Albertyn

2006

Yeast

View full text Add to dashboard Cite

Epoxide hydrolases (EHs), especially those of fungal origin, have the ability to catalyse the enantioselective hydrolysis of epoxides to their corresponding diols. Recombinant DNA technology has been used extensively to overproduce these catalysts for the efficient hydrolytic kinetic resolution of epoxides, which serve as high-value intermediates in the fine chemicals and pharmaceutical industries. Degenerate primers, based on data from available EH-encoding gene sequences, in conjunction with inverse PCR, were used to amplify the genomic EH-encoding gene from Rhodotorula mucilaginosa. The 2347 bp genomic sequence revealed a 1979 bp ORF containing nine introns. The cDNA sequence revealed an 1185 bp EH-encoding gene that translates into a 394 amino acid protein exhibiting low sequence homology towards the known EH proteins. The EH gene from R. mucilaginosa was functionally expressed in Yarrowia lipolytica using a constitutive integrative expression cassette. Whole-cell biotransformation of (2,3-epoxypropyl)benzene, using the recombinant EH, revealed activity and selectivity far superior to any other activity and selectivity reported in literature using wild-type organisms. The GenBank Accession No. for the R. mucilaginosa EH gene is AY627310.

show abstract

Section: Construction Of a Constitutive Y Lipolytica Integrative Vecsupporting

confidence: 68%

Section: Introductionmentioning

confidence: 99%

Cloning of an epoxide hydrolase‐encoding gene from Rhodotorula mucilaginosa and functional expression in Yarrowia lipolytica

Labuschagne

Albertyn

2006

Yeast

View full text Add to dashboard Cite

show abstract

“…We are therefore turning our attention to substrates that are not converted by the Jacobsen catalysts or epoxide hydrolases (64).…”

Section: Directed Evolution Of Other Enzymesmentioning

confidence: 99%

Controlling the enantioselectivity of enzymes by directed evolution: Practical and theoretical ramifications

Reetz

2004

Proc. Natl. Acad. Sci. U.S.A.

316

177

View full text Add to dashboard Cite

A fundamentally new approach to asymmetric catalysis in organic chemistry is described based on the in vitro evolution of enantioselective enzymes. It comprises the appropriate combination of gene mutagenesis and expression coupled with an efficient high-throughput screening system for evaluating enantioselectivity (enantiomeric excess assay). Several such cycles lead to a ''Darwinistic'' process, which is independent of any knowledge concerning the structure or the mechanism of the enzyme being evolved. The challenge is to choose the optimal mutagenesis methods to navigate efficiently in protein sequence space. As a first example, the combination of error-prone mutagenesis, saturation mutagenesis, and DNA-shuffling led to a dramatic enhancement of enantioselectivity of a lipase acting as a catalyst in the kinetic resolution of a chiral ester. Mutations at positions remote from the catalytically active center were identified, a surprising finding, which was explained on the basis of a novel relay mechanism. The scope and limitations of the method are discussed, including the prospect of directed evolution of stereoselective hybrid catalysts composed of robust protein hosts in which transition metal centers have been implanted.

show abstract

“…Fatty acid epoxides interact enantioselectively with many proteins including P450 epoxygenases and epoxide hydrolases (Orru and Faber, 1999). In the present study, the epoxide is a critical functional group in EETs, which activates K ATP channels.…”

Section: Stereospecific Activation Of Cardiac K Atp Channels By Eets mentioning

confidence: 83%

Stereospecific Activation of Cardiac ATP-Sensitive K⁺Channels by Epoxyeicosatrienoic Acids: A Structural Determinant Study

2002

View full text Add to dashboard Cite

The heart is richly endowed with K ATP channels, which function as biological sensors, regulating membrane potentials and electrical excitability in response to metabolic alterations. We recently reported that the cytochrome P450 metabolites of arachidonic acid, epoxyeicosatrienoic acids (EETs), potently activate cardiac K ATP channels by reducing channel sensitivity to ATP. In the present study, we further demonstrate that 11(S),12(R)-EET activated the cardiac K ATP channels with an EC 50 of 39.5 nM, whereas 11(R),12(S)-EET was totally inactive. In addition, 11(S),12(R)-EET but not 11(R),12(S)-EET hyperpolarized the resting membrane potentials and shortened the duration of cardiomyocyte action potentials. By studying homologs and analogs of 11,12-EET, we also found that all four EET regioisomers are equipotent activators of the K ATP channels, reducing the ATP sensitivity by more than 10-fold; however, neither altered chain length, double bond number, epoxide position, nor methylation of the carboxyl group affected channel inhibitions by ATP. All the fatty epoxides studied are potent K ATP channel activators, but the -3 homolog was particularly potent, reducing ATP sensitivity 27-fold. Together, the results indicate that the presence of an epoxide group in a particular three-dimensional configuration is a critical determinant for K ATP channel activation, and its effect is augmented by a double bond at -3 position. The results also suggest that fatty epoxides are important modulators of cardiac electrical excitability.

show abstract

Stereoselectivities of microbial epoxide hydrolases

Cited by 63 publications

References 29 publications

Cloning of an epoxide hydrolase‐encoding gene from Rhodotorula mucilaginosa and functional expression in Yarrowia lipolytica

Cloning of an epoxide hydrolase‐encoding gene from Rhodotorula mucilaginosa and functional expression in Yarrowia lipolytica

Controlling the enantioselectivity of enzymes by directed evolution: Practical and theoretical ramifications

Stereospecific Activation of Cardiac ATP-Sensitive K⁺Channels by Epoxyeicosatrienoic Acids: A Structural Determinant Study

Contact Info

Product

Resources

About

Stereoselectivities of microbial epoxide hydrolases

Cited by 63 publications

References 29 publications

Cloning of an epoxide hydrolase‐encoding gene from Rhodotorula mucilaginosa and functional expression in Yarrowia lipolytica

Cloning of an epoxide hydrolase‐encoding gene from Rhodotorula mucilaginosa and functional expression in Yarrowia lipolytica

Controlling the enantioselectivity of enzymes by directed evolution: Practical and theoretical ramifications

Stereospecific Activation of Cardiac ATP-Sensitive K+Channels by Epoxyeicosatrienoic Acids: A Structural Determinant Study

Contact Info

Product

Resources

About

Stereospecific Activation of Cardiac ATP-Sensitive K⁺Channels by Epoxyeicosatrienoic Acids: A Structural Determinant Study