Enzymatic production of Cilastatin intermediate via highly enantioselective hydrolysis of methyl (±)-2,2-dimethylcyclopropane carboxylate using newly isolated Rhodococcus sp. ECU1013

Appl Microbiol Biotechnol. 2013 Sep;97(17):7659-67. doi: 10.1007/s00253-013-5038-z. Epub 2013 Jun 27.

Abstract

(S)-(+)-2,2-Dimethylcyclopropane carboxylic acid [(S)-(+)-DMCPA] is a key chiral intermediate for production of Cilastatin, an excellent renal dehydropeptidase-I inhibitor. In this study, a new method for preparation of (S)-(+)-DMCPA with microbial esterases was investigated. A microbial screening program obtained six esterase-producing isolates that could display relatively high activities and enantioselectivities using racemic ethyl 2,2-dimethylcyclopropane carboxylate (DMCPE) as screening substrate, aiming at forming optically pure (S)-(+)-DMCPA. Further selection was carried out with substrates having different alcohol moieties, including methyl, ethyl, and 2-chloroethyl esters. Finally, one of these strains, numbered ECU1013, with high enantioselectivity toward the hydrolytic resolution of methyl 2,2-dimethylcyclopropane carboxylate (DMCPM), afforded the (S)-product in 92 % ee, and was later identified as Rhodococcus sp. According to our research, there were several active esterases to DMCPM in cells of Rhodococcus sp. ECU1013; however, (S)-preferential esterase was selectively enriched based on the time-dependent profile of esterases biosynthesis, thereby the enantiomeric excess of biotransformation product (ee p) was constantly increased, finally maintained at 95 % (S). To improve the yield, various organic solvents were employed for better dispersion of the hydrophobic substrate. As a result, (±)-DMCPM of up to 400 mM in the organic phase of isooctane was enantioselectively hydrolyzed into (S)-(+)-DMCPA, with an isolation yield of 38 % and a further increase of ee p to 99 %.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Cilastatin / metabolism*
  • Cyclopropanes / chemistry
  • Cyclopropanes / metabolism*
  • Esterases / genetics
  • Esterases / metabolism
  • Hydrolysis
  • Molecular Sequence Data
  • Phylogeny
  • Rhodococcus / classification
  • Rhodococcus / enzymology
  • Rhodococcus / isolation & purification
  • Rhodococcus / metabolism*
  • Soil Microbiology
  • Stereoisomerism

Substances

  • Bacterial Proteins
  • Cyclopropanes
  • Cilastatin
  • 1,2-dimethylcyclopropane
  • Esterases