scholarly journals Molecular engineering of epoxide hydrolase and its application to asymmetric and enantioconvergent hydrolysis

2007 ◽  
Vol 98 (2) ◽  
pp. 318-327 ◽  
Author(s):  
Eun Yeol Lee ◽  
Michael L. Shuler
Keyword(s):  
Epoxide Hydrolase ◽  
Molecular Engineering ◽  
Enantioconvergent Hydrolysis

scholarly journals Substantially improving the enantioconvergence of PvEH1, a Phaseolus vulgaris epoxide hydrolase, towards m-chlorostyrene oxide by laboratory evolution

2019 ◽  
Vol 18 (1) ◽  
Author(s):  
Xun-Cheng Zong ◽  
Chuang Li ◽  
Yao-Hui Xu ◽  
Die Hu ◽  
Bo-Chun Hu ◽  
...  
Keyword(s):  
Phaseolus Vulgaris ◽  
Epoxide Hydrolase ◽  
Substrate Binding ◽  
Binding Pocket ◽  
Saturation Mutagenesis ◽  
Substrate Binding Pocket ◽  
Laboratory Evolution ◽  
E Coli ◽  
Enantioconvergent Hydrolysis ◽  
Hydrolysis Of

Abstract Background Epoxide hydrolase can regioselectively catalyze the oxirane ring-opening hydrolysis of rac-epoxides producing the corresponding chiral diols. In our laboratory, a gene named pveh1 encoding an EH from Phaseolus vulgaris was cloned. Although the directed modification of PvEH1 was carried out, the mutant PvEH1Y3 showed a limited degree of enantioconvergence towards racemic (rac-) m-chlorostyrene oxide (mCSO). Results PvEH1 and PvEH1Y3 were combinatively subjected to laboratory evolution to further enhance the enantioconvergence of PvEH1Y3 towards rac-mCSO. Firstly, the substrate-binding pocket of PvEH1 was identified using a CAVER 3.0 software, and divided into three zones. After all residues in zones 1 and 3 were subjected to leucine scanning, two E. coli transformants, E. coli/pveh1Y149L and /pveh1P184L, were selected, by which rac-mCSO was transformed into (R)-m-chlorophenyl-1,2-ethanediol (mCPED) having 55.1% and 27.2% eep. Secondly, two saturation mutagenesis libraries, E. coli/pveh1Y149X and /pveh1P184X (X: any one of 20 residues) were created at sites Y149 and P184 of PvEH1. Among all transformants, both E. coli/pveh1Y149L (65.8% αS and 55.1% eep) and /pveh1P184W (66.6% αS and 59.8% eep) possessed the highest enantioconvergences. Finally, the combinatorial mutagenesis was conducted by replacements of both Y149L and P184W in PvEH1Y3, constructing E. coli/pveh1Y3Z2, whose αS reached 97.5%, higher than that (75.3%) of E. coli/pveh1Y3. In addition, the enantioconvergent hydrolysis of 20 mM rac-mCSO was performed by E. coli/pveh1Y3Z2, giving (R)-mCPED with 95.2% eep and 97.2% yield. Conclusions In summary, the enantioconvergence of PvEH1Y3Z2 was successfully improved by laboratory evolution, which was based on the study of substrate-binding pocket by leucine scanning. Our present work introduced an effective strategy for the directed modification of enantioconvergence of PvEH1.

Previously published / Prédémment paruAsymmetric total synthesis of (+)-exo-brevicomin based on enantioconvergent biocatalytic hydrolysis of an alkene-functionalized 2,3-disubstituted epoxide

2002 ◽  
Vol 80 (6) ◽  
Author(s):  
Sandra F Mayer ◽  
Harald Mang ◽  
Andreas Steinreiber ◽  
Robert Saf ◽  
Kurt Faber
Keyword(s):  
Total Synthesis ◽  
Asymmetric Synthesis ◽  
Bark Beetle ◽  
Epoxide Hydrolase ◽  
Side Chains ◽  
Beetle Species ◽  
Epoxide Hydrolases ◽  
Pheromone System ◽  
Enantioconvergent Hydrolysis ◽  
Hydrolysis Of

A short total asymmetric synthesis of (+)-exo- and (–)-endo-brevicomin ((+)-exo-3 and (–)-endo-3), which are components of the attracting pheromone system of several bark-beetle species belonging to the genera Dendroctonus and Dryocoetes, was accomplished via a chemoenzymatic protocol. The key step consisted of biocatalytic hydrolysis by bacterial epoxide hydrolases of cis-configured 2,3-disubstituted oxiranes bearing olefinic side chains. This reaction proceeded in an enantioconvergent fashion, by affording a single enantiomeric vic-diol from the rac-epoxide in up to 92% ee and 83% isolated yield.Key words: bacterial epoxide hydrolase, 2,3-disubstituted oxirane, enantioconvergent hydrolysis, (+)-exo-brevicomin, (–)-endo-brevicomin.

Asymmetric total synthesis of (+)-exo-brevicomin based on enantioconvergent biocatalytic hydrolysis of an alkene-functionalized 2,3-disubstituted epoxide

2002 ◽  
Vol 80 (4) ◽  
pp. 362-369 ◽  
Author(s):  
Sandra F Mayer ◽  
Harald Mang ◽  
Andreas Steinreiber ◽  
Robert Saf ◽  
Kurt Faber
Keyword(s):  
Total Synthesis ◽  
Asymmetric Synthesis ◽  
Bark Beetle ◽  
Epoxide Hydrolase ◽  
Beetle Species ◽  
Asymmetric Total Synthesis ◽  
Epoxide Hydrolases ◽  
Pheromone System ◽  
Enantioconvergent Hydrolysis ◽  
Hydrolysis Of

A short total asymmetric synthesis of (+)-exo- and (–)-endo-brevicomin ((+)-exo-3 and (–)-endo-3), which are components of the attracting pheromone system of several bark-beetle species belonging to the genera Dendroctonus and Dryocoetes, was accomplished via a chemoenzymatic protocol. The key step consisted of biocatalytic hydrolysis by bacterial epoxide hydrolases of cis-configured 2,3-disubstituted oxiranes bearing olefinic side chains. This reaction proceeded in an enantioconvergent fashion, by affording a single enantiomeric vic-diol from the rac-epoxide in up to 92% ee and 83% isolated yield.Key words: bacterial epoxide hydrolase, 2,3-disubstituted oxirane, enantioconvergent hydrolysis, (+)-exo-brevicomin, (–)-endo-brevicomin.

scholarly journals Conformational diversity and enantioconvergence in potato epoxide hydrolase 1

2016 ◽  
Vol 14 (24) ◽  
pp. 5639-5651 ◽  
Author(s):  
P. Bauer ◽  
Å. Janfalk Carlsson ◽  
B. A. Amrein ◽  
D. Dobritzsch ◽  
M. Widersten ◽  
...  
Keyword(s):  
Epoxide Hydrolase ◽  
Styrene Oxide ◽  
Computational Studies ◽  
Conformational Diversity ◽  
Enantioconvergent Hydrolysis ◽  
Hydrolysis Of

Computational studies highlight the importance of conformational diversity in the enantioconvergent hydrolysis of styrene oxide by potato epoxide hydrolase 1.

Fluorescence ratio imaging of dynamic intracellular ionic signals

1988 ◽  
Vol 46 ◽  
pp. 42-43
Author(s):  
R. Y. Tsien ◽  
A. Minta ◽  
M. Poenie ◽  
J.P.Y. Kao ◽  
A. Harootunian
Keyword(s):  
Binding Sites ◽  
Living Cells ◽  
Molecular Engineering ◽  
Ph Indicators ◽  
Highly Sensitive ◽  
Fluorescence Ratio Imaging ◽  
Ratio Imaging ◽  
Technical Advances ◽  
Indicator Dyes ◽  
Fluorescein Dyes

Recent technical advances now enable the continuous imaging of important ionic signals inside individual living cells with micron spatial resolution and subsecond time resolution. This methodology relies on the molecular engineering of indicator dyes whose fluorescence is strong and highly sensitive to ions such as Ca2+, H+, or Na+, or Mg2+. The Ca2+ indicators, exemplified by fura-2 and indo-1, derive their high affinity (Kd near 200 nM) and selectivity for Ca2+ to a versatile tetracarboxylate binding site3 modeled on and isosteric with the well known chelator EGTA. The most commonly used pH indicators are fluorescein dyes (such as BCECF) modified to adjust their pKa's and improve their retention inside cells. Na+ indicators are crown ethers with cavity sizes chosen to select Na+ over K+: Mg2+ indicators use tricarboxylate binding sites truncated from those of the Ca2+ chelators, resulting in a more compact arrangement of carboxylates to suit the smaller ion.

Combinatorial Peptide Libraries for Selecting Inorganic-Binding Proteins: A Step in Molecular Biomimetics

2003 ◽  
Vol 773 ◽  
Author(s):  
C. Tamerler ◽  
S. Dinçer ◽  
D. Heidel ◽  
N. Karagûler ◽  
M. Sarikaya
Keyword(s):  
Binding Proteins ◽  
Building Blocks ◽  
Molecular Engineering ◽  
Inorganic Materials ◽  
Combinatorial Peptide Libraries ◽  
Self Assembling ◽  
Complex Functions ◽  
Recent Developments ◽  
Specific Proteins ◽  
Molecular Biomimetics

AbstractProteins, one of the building blocks in organisms, not only control the assembly in biological systems but also provide most of their complex functions. It may be possible to assemble materials for practical technological applications utilizing the unique advantages provided by proteins. Here we discuss molecular biomimetic pathways in the quest for imitating biology at the molecular scale via protein engineering. We use combinatorial biology protocols to select short polypeptides that have affinity to inorganic materials and use them in assembling novel hybrid materials. We give an overview of some of the recent developments of molecular engineering towards this goal. Inorganic surface specific proteins were identified by using cell surface and phage display technologies. Examples of metal and metal oxide specific polypeptides were represented with an emphasis on certain level of specificities. The recognition and self assembling characteristics of these inorganic-binding proteins would be employed in develeopment of hybrid multifunctional materials for novel bio- and nano-technological applications.

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