Case Studies

PRODUCTION OF SEMISYNTHETIC ANTIBIOTICS

GENERAL: Semisynthetic antibiotics show excellent therapeutic value against various resistant pathogenic microbial strains. Today, thousands of semisynthetic β-lactam antibiotics are being synthesised from 6-aminipenicillanic acid (6-APA) or 7 – aminodesacetoxycephalosporanic acid (7-ADCA). These two important intermediates are nowadays mainly produced by an enzymatic deacylation method using penicillin amidase (EC 3.5.1.11) from penicillin G or V.

Due to the difficulty and the cost of the enzyme isolation from any specific bacterial strain and also due to the enzyme's low stability, the immobilisation of the enzyme is often applied in order to fully utilise the enzyme's lifetime in its whole length and in order to increase the stability of the biomaterial. Moreover, the immobilised enzyme can be easily separated from the reaction media. However, the process of immobilisation often results in a dramatic decrease in the enzyme's activity caused by the limited diffusion of the reactant to the active centre of the enzyme or into the immobilisation matrix itself. Therefore, there is an ongoing demand for an immobilisation technique unburdened by this negative effect on the enzyme's activity, yet still offering the advantages on the immobilisation process.

SOLUTION: LentiKat’s has developed a Biocatalyst with the penicillin G acylase activity using E. coli as the source of the enzymatic material. The Biocatalyst achieves 98-99% conversion rate at 28°C and pH 8.5 while processing 8% w/v solution of penicillin G. The time of one conversion is from 80 to 120 minutes.

ADVANTAGES:

  • 30% longer lifetime of the Biocatalyst of up to 800-900 conversions,
  • high specific activity of up to 650 U/g dw (85 U/g ww),
  • specific productivity of 1,150 kg 6-APA/kg ww,
  • superb enzyme stability,
  • excellent mechanical characteristics of the matrix,
  • convenient size for easy separation,
  • low diffusion limitation,
  • high conversion efficiency.

GUARANTEED VALUES:

  • specific activity: 70 U/g ww (400 U/g dw),
  • minimum of 800 repeated conversions.

Back