title: Resolution of racemic sulfoxides with high productivity and enantioselectivity by a Rhodococcus sp. strain as an alternative to biooxidation of prochiral sulfides for efficient production of enantiopure sulfoxides.
abstract: Whole cells of Rhodococcus sp. ECU0066 were used a catalyst for resolution of racemic sulfoxides, as an alternative to asymmetric oxidation of sulfides for efficient production of enantiopure sulfoxides. Racemic sulfoxides were excellent substrates for biotransformation because of their lower biotoxicity compared to sulfides. Determination of apparent kinetic parameters indicated that phenyl methyl sulfide (PMS), but not racemic phenyl methyl sulfoxide (rac-PMSO) caused substrate inhibition. (S)-PMSO was formed at a higher concentration and good enantiomeric excess (37.8 mM and 93.7% ee(S)) in a fed-batch reaction, than by an asymmetric oxidation of PMS (10 mM and 80% eeP (S)). The bacterium also displayed fairly good activity (yields, 22.7-43.2%; within 1-8 h) and enantioselectivity (ee(S)>99.0%) towards para-substituted (methyl and chloro) phenyl methyl sulfoxides and ethyl phenyl sulfoxide, indicating it could be a promising agent for synthetic applications.
authors.affiliation: Laboratory of Biocatalysis and Bioprocessing, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China.
authors.forename: Ai-Tao
authors.initials: AT
authors.lastname: Li
authors.forename: Hui-Lei
authors.initials: HL
authors.lastname: Yu
authors.forename: Jiang
authors.initials: J
authors.lastname: Pan
authors.forename: Jian-Dong
authors.initials: JD
authors.lastname: Zhang
authors.forename: Jian-He
authors.initials: JH
authors.lastname: Xu
authors.forename: Guo-Qiang
authors.initials: GQ
authors.lastname: Lin
mesh_terms: D002384:Catalysis; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D050296:Microbial Viability; D010084:Oxidation-Reduction; D012240:Rhodococcus / Q000166:cytology / Q000378:metabolism*; D013237:Stereoisomerism; D013379:Substrate Specificity; D013440:Sulfides / Q000737:chemistry* / Q000378:metabolism*; D013454:Sulfoxides / Q000138:chemical synthesis* / Q000737:chemistry* / Q000378:metabolism; D013696:Temperature; D013997:Time Factors
chemical_list: D013440:Sulfides; D013454:Sulfoxides; C417240:methyl phenyl sulfoxide; C093850:methylphenylsulfide