title: Continuous production of chiral 1,3-butanediol using immobilized biocatalysts in a packed bed reactor: promising biocatalysis method with an asymmetric hydrogen-transfer bioreduction.
abstract: An asymmetric hydrogen-transfer biocatalyst consisting of mutated Rhodococcus phenylacetaldehyde reductase (PAR) or Leifsonia alcohol dehydrogenase (LSADH) was applied for some water-soluble ketone substrates. Among them, 4-hydroxy-2-butanone was reduced to (S)/(R)-1,3-butanediol, a useful intermediate for pharmaceuticals, with a high yield and stereoselectivity. Intact Escherichia coli cells overexpressing mutated PAR (Sar268) or LSADH were directly immobilized with polyethyleneimine or 1,6-diaminehexane and glutaraldehyde and evaluated in a batch reaction. This system produced (S)-1,3-butanediol [87% enantiomeric excess (e.e.)] with a space time yield (STY) of 12.5 mg h(-1) ml(-1) catalyst or (R)-1,3-butanediol (99% e.e.) with an STY of 60.3 mg h(-1) ml(-1) catalyst, respectively. The immobilized cells in a packed bed reactor continuously produced (R)-1,3-butanediol with a yield of 99% (about 49.5 g/l) from 5% (w/v) 4-hydroxy-2-butanoate over 500 h.
authors: Department of Biotechnology, Faculty of Engineering (Biotechnology Research Center), Toyama Prefectural University, Kurokawa 5180, Imizu, Toyama 939-0398, Japan. itoh@pu-toyama.ac.jp
authors: Nobuya
authors: N
authors: Itoh
authors: Masatoshi
authors: M
authors: Nakamura
authors: Kousuke
authors: K
authors: Inoue
authors: Yoshihide
authors: Y
authors: Makino
mesh_terms: D019840:2-Propanol / Q000737:chemistry / Q000378:metabolism; D019149:Bioreactors; D002072:Butylene Glycols / Q000737:chemistry / Q000378:metabolism*; D018914:Cells, Immobilized; D004926:Escherichia coli / Q000378:metabolism*; D006859:Hydrogen / Q000378:metabolism*; D008968:Molecular Conformation; D010084:Oxidation-Reduction; D013379:Substrate Specificity
chemical_list: D002072:Butylene Glycols; C028491:1,3-butylene glycol; D006859:Hydrogen; D019840:2-Propanol