title: Enantioselective transesterification using immobilized Aspergillus oryzae overexpressing lipase.
abstract: In the present study, we used gene manipulation to construct a recombinant Aspergillus oryzae strain overexpressing lipase and investigated its application to the optical resolution of chiral compounds. A. oryzae niaD300, which was derived from the wild-type strain RIB40, was used as the host strain. The tglA gene, which encodes a triacylglycerol lipase, was cloned from the A. oryzae niaD300 chromosomal genome, then reintroduced, with and without a secretion-signal sequence, into the genome and expressed under the control of the improved glaA promoter of plasmid pNGA142. The resulting recombinant strain overexpressing A. oryzae lipase was immobilized within biomass-support particles and used as a whole-cell biocatalyst. The immobilized lipase-overexpressing strain with secretion-signal sequence showed high activity and was used to selectively synthesize (R)-1-phenylethyl acetate from (RS)-1-phenylethanol and vinyl acetate. After 48 h reaction at 30 degrees C with molecular sieve 4A, the yield and enantiomeric excess (%ee) of (R)-1-phenylethyl acetate reached approximately 90 and 95%ee, respectively. The whole-cell biocatalyst for optical resolution of chiral compounds produced in this study maintained its activity over 25 batch-reaction cycles.
authors.affiliation: Division of Molecular Science, Graduate School of Science and Technology, Kobe University, 1-1 Rokkoudai, Nada, Kobe, 657-8501, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Kaieda
authors.forename: M
authors.initials: M
authors.lastname: Nagayoshi
authors.forename: S
authors.initials: S
authors.lastname: Hama
authors.forename: A
authors.initials: A
authors.lastname: Kondo
authors.forename: H
authors.initials: H
authors.lastname: Fukuda
mesh_terms: D001236:Aspergillus oryzae / Q000201:enzymology* / Q000235:genetics; D018914:Cells, Immobilized / Q000201:enzymology / Q000378:metabolism; D004951:Esterification; D015966:Gene Expression Regulation, Fungal; D008049:Lipase / Q000235:genetics / Q000378:metabolism*; D010626:Phenylethyl Alcohol / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism*; D013237:Stereoisomerism; D014753:Vinyl Compounds / Q000378:metabolism
chemical_list: D011994:Recombinant Proteins; D014753:Vinyl Compounds; D008049:Lipase; C011566:vinyl acetate; D010626:Phenylethyl Alcohol