Crosslinked penicillin acylase aggregates for synthesis of β-lactam antibiotics in organic medium

Andrés Illanes, LORENA EVELYN WILSON SOTO, Eduardo Caballero, Roberto Fernández-Lafuente, José Manuel Guisán

Research output: Contribution to journalArticlepeer-review

43 Scopus citations

Abstract

Crosslinked enzyme aggregates (CLEAs) of a partially purified penicillin acylase from a recombinant Escherichia coli strain have been produced as a novel type of biocatalysts well endowed to perform in organic media. Different protein precipitants were studied and glutaraldehyde was used as the crosslinking agent. Precipitation curves were obtained for all precipitants to determine the concentrations at which all the protein precipitated out of the solution. The effect of the glutaraldehyde-to-protein ratio was studied with respect to process recovery and the specific activity and stability of the biocatalyst. Recovery of penicillin acylase activity was moderately high, about 50%; major losses of enzyme activity were produced at the precipitation step. Specific activities of all CLEAs were very high, which is one of the advantages of using nonsupported biocatalysts. Ammonium sulfate and tert-butyl alcohol were the best precipitants at a glutaraldehyde-protein mass ratio of 2 and were selected to perform the kinetically controlled synthesis of ampicillin in 60% (v/v) ethylene glycol medium. At comparable conversion yields, volumetric and specific antibiotic productivity were much higher for CLEAs than for carrier-bound penicillin acylases.

Original languageEnglish
Pages (from-to)189-202
Number of pages14
JournalApplied Biochemistry and Biotechnology
Volume133
Issue number3
DOIs
StatePublished - Jun 2006
Externally publishedYes

Keywords

  • β-lactam antibiotics
  • Ampicillin
  • Crosslinked enzyme aggregates
  • Enzyme immobilization
  • Organic cosolvents
  • Penicillin acylase

Fingerprint Dive into the research topics of 'Crosslinked penicillin acylase aggregates for synthesis of β-lactam antibiotics in organic medium'. Together they form a unique fingerprint.

Cite this