Search PubMed for references concerning: (R,S)-DMPM
Title: A Novel esterase from Pseudochrobactrum asaccharolyticum WZZ003: Enzymatic properties toward model substrate and catalytic performance in chiral fungicide intermediate synthesis Cheng F, Zheng J, Wu G, Zhang Y, Wang Z Ref: Process Biochemistry, 69:92, 2018 : PubMed
Only a few esterases have been used for the synthesis of optically pure fungicide. For example, (R)-metalaxyl synthesized using esterase-involved bioreaction displays fungicide activity, whereas (S)-enantiomer is redundant. However, the biosynthesis of (R)-metalaxyl is currently hampered by the lower activity, selectivity and thermostability of esterase. Therefore, to obtain a better biocatalyst, several esterase genes were cloned from Pseudochrobactrum asaccharolyticum WZZ003. The esterase PAE07, among eight enzymes, was selected because it exhibited the highest hydrolysis activity toward (R,S)-DMPM. The DNA and amino acid sequence analysis suggested that PAE07 is a new member of lipolytic enzyme family V. The enzymatic properties of PAE07 toward (R,S)-DMPM and model substrate (p-nitrophenyl acetate) were investigated. PAE07 was found to be a highly active esterase with excellent enantioselectivity. The reaction conditions including temperatureand pH were optimized, and the effects of metal ions, organic solvents and detergents were also investigated. Results indicated that PAE07 is a competitive candidate for (R)-metalaxyl manufacturing.
        
Title: Stereoselective lipases from Burkholderia sp., cloning and their application to preparation of methyl (R)-N-(2,6-dimethylphenyl)alaninate, a key intermediate for (R)-Metalaxyl Park OJ, Lee SH Ref: J Biotechnol, 120:174, 2005 : PubMed
Two microbial strains (referred to as MC 16-3 and 99-2-1) that produce extracellular lipases were isolated from soil samples and identified as Burkholderia species. The lipases were partially purified by isopropyl alcohol precipitation and gave molecular weight of 33kDa. The lipases were characterized in terms of stereoselectivity with racemic methoxyethyl (R,S)-N-(2,6-dimethylphenyl)alaninate and the genes encoding the proteins have been identified by homology alignment of lipases reported belonging to I.2 subfamily and their complete DNA sequences were determined. The lipases will be useful for the preparation of methyl (R)-N-(2,6-dimethylphenyl)alaninate, a key intermediate for the synthesis of (R)-Metalaxyl, which is one of the best-selling fungicides.