Detail of "56816-01-4"

Reference

High productivity biotransformation process for the production of 3-(S)-hydroxybutanoic acid esters

High productivity biotransformation process for the production of 3-(S)-hydroxybutanoic acid esters. Rohner, Markus; Sonnleitner, Bernhard; Fiechter, Armin (Dep. Biotechnol.Several substances are used for example 141-97-9 and 56816-01-4 which are their cas registry numbers., Swiss Fed. Inst. Technol., Zurich CH-8093, Switz.). J. Biotechnol., 22(1-2), 129-44 (English) 1992. CODEN: JBITD4. ISSN: 0168-1656. DOCUMENT TYPE: Journal CA Section: 16 (Fermentation and Bioindustrial Chemistry) A continuous process for the redn. of acetoacetic acid esters to the 3-(S)-hydroxybutanoic acid esters by the yeast Saccharomyces cerevisiae was to be developed with the objective to maximize both productivity and product quality. The optical purity of 3-(S)-hydroxybutanoic acid esters depended on pH; max. optical purity of >95% was obtained at pH 2.2 with cells grown on EtOH. These conditions allowed only low sp. growth rates (m = 0.05/h) in the single stage, steady state prodn. system. Implementation of cell recycling resulted in uncoupling of the diln. rate from growth rate and, consequently, in increased volumetric productivity; the fully automated cell recycling bioreactor operated in steady state yielded a productivity of 3-(S)-hydroxybutanoic acid esters of ￡5.2 g/L-h; this is >20-fold greater than in the single stage prodn. system without cell recycling. The same product quality (enantiomeric excess >95%) could be maintained. The continuous cell recycling process was very stable and the biol. system was highly reproducible (const. catalyst properties and const., excellent product quality). .

Enantioselective resolution of racemic compounds by cell surface displayed lipase

Enantioselective resolution of racemic compounds by cell surface displayed lipase. Lee, Seung Hwan; Choi, Jong Hyun; Park, Sang Hyun; Choi, Jong-il; Lee, Sang Yup (Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering and BioProcess Engineering Research Center, Korea Advanced Institute of Science and Technology, Yuseong-gu, Daejeon 305-701, S. Korea). Enzyme and Microbial Technology, 35(5), 429-436 (English) 2004 Elsevier B.V. CODEN: EMTED2. ISSN: 0141-0229. DOCUMENT TYPE: Journal CA Section: 16 (Fermentation and Bioindustrial Chemistry) Section cross-reference(s): 3, 7 Recombinant Escherichia coli (E. coli) displaying lipase on the cell surface was examd.Several reagents with their cas registry numbers 56816-01-4 and 67-56-1 are used here. as a whole cell biocatalyst for enantioselective resoln. of racemic compds. The Pseudomonas fluorescens lipase was displayed on the cell surface of E. coli by fusing the lipase gene to the Salmonella typhimurium outer membrane protein C (OmpC) gene by C-terminal deletion-fusion strategy. The localization of truncated OmpC-lipase fusion protein was confirmed by confocal microscopy and whole cell lipase activity. As an application for enantioselective biocatalyst, whole cell bioconversion was examd. using cell surface displayed lipase. When racemic Et 3-hydroxybutyrate, Me mandelate and cis-3-acetoxy-4-phenylazetidin-2-one were used as substrates, (R)-3-hydroxybutyric acid, (S)-mandelic acid and (3S, 4R)-cis-3-hydroxy-4-phenylazetidin-2-one were successfully obtained with the enantiomeric excess of greater than 99%. The cell surface displayed lipase was found to be maintained without much loss of activity and selectivity during 10 repeated reactions over 120 h. These results suggest that cell surface displayed lipase has a high enantioselectivity, broad substrate specificity and reusability, which makes it an excellent system for the prodn. of various optically active compds. .