Bioresolution of racemic phenyl glycidyl ether by a putative recombinant epoxide hydrolase from Streptomyces griseus NBRC 13350

• Published in: World journal of microbiology & biotechnology Vol. 33; no. 5; pp. 82 - 15
• Main Authors: Saini, Priya, Kumar, Naveen, Wani, Shadil Ibrahim, Sharma, Shilpi, Chimni, Swapandeep Singh, Sareen, Dipti
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.05.2017; Springer Nature B.V
• Subjects: Affinity chromatography; Applied Microbiology; Biochemistry; Biomedical and Life Sciences; Biotechnology; Chemicals; Chromatography, Gel; Cloning, Molecular; Dimethylformamide; E coli; Environmental Engineering/Biotechnology; Epoxide hydrolase; Epoxide Hydrolases - genetics; Epoxide Hydrolases - metabolism; Epoxides; Escherichia coli; Escherichia coli - genetics; Ethers; Genes; Genomes; Kinetics; Life Sciences; Microbiology; Nucleotide sequence; Original Paper; Phenyl Ethers - metabolism; Phenyls; Reaction time; Recombinant; Recombinant Proteins - metabolism; Stereoisomerism; Streptomyces griseus; Streptomyces griseus - enzymology; Streptomyces griseus - genetics; Substrate Specificity; Substrates; Wet cells; Yield; Recombinant protein; Bioresolution; Phenyl glycidyl ether; Epoxide hydrolase; NBRC 13350; Streptomyces griseus NBRC 13350
• ISSN: 0959-3993; 1573-0972
• DOI: 10.1007/s11274-017-2248-z

In order to produce enantiomerically pure epoxides for the synthesis of value-added chemicals, a novel putative epoxide hydrolase (EH) sgeh was cloned and overexpressed in pET28a/ Escherichia coli BL21(DE3). The 1047 bp sgeh gene was mined from Streptomyces griseus NBRC 13350 genome sequence. The recombinant hexahistidyl-tagged SGEH was purified (16.6-fold) by immobilized metal-affinity chromatography, with 90% yield as a homodimer of 100 kDa. The recombinant E. coli whole cells overexpressing SGEH could kinetically resolve racemic phenyl glycidyl ether (PGE) into ( R )-PGE with 98% ee, 40% yield, and enantiomeric ratio (E) of 20. This was achieved under the optimized reaction conditions i.e. cell/substrate ratio of 20:1 (w/w) at pH 7.5 and 20 °C in 10% (v/v) dimethylformamide (DMF) in a 10 h reaction. 99% enantiopure ( R )-PGE was obtained when the reaction time was prolonged to 12 h with a yield of 34%. In conclusion, an economically viable and environment friendly green process for the production of enantiopure ( R )-PGE was developed by using wet cells of E. coli expressing recombinant SGEH.