Penicillin acylase-catalyzed synthesis of N-bromoacetyl-7-aminocephalosporanic acid, the key intermediate for the production of cefathiamidine

Abstract

BackgroundEnzymatic approaches have become promising alternatives to chemical methods for the production of semi-synthetic β-lactam antibiotics. In this work, enzymatic synthesis of N-bromoacetyl-7-aminocephalosporanic acid (N-bromoacetyl-7-ACA), the key intermediate for the production of cefathiamidine, was reported for the first time.ResultsOf the immobilized penicillin acylases (PAs) tested, PGA-750 was the best biocatalyst. Optimization of the biocatalytic process was conducted. The optimal acyl donor, molar ratio of acyl donor to 7-ACA, pH, temperature, 7-ACA concentration, and enzyme dosage were methyl bromoacetate, 3, 7.5, 20 °C, 50 mmol/L and 4 U/mL, respectively. Under the optimal conditions, enzymatic N-acylation of 7-ACA with methyl bromoacetate afforded the desired product with the yield of 85% in 2 h, where the synthesis/hydrolysis (S/H) ratio was approximately 1.5. The immobilized enzyme PGA-750 exhibited good operational stability, and the relative yields of approximately 90% and 63% were achieved, respectively, when it was reused in 7th and 11th batch.ConclusionsAn enzymatic approach to N-bromoacetyl-7-ACA, the key intermediate for the industrial production of cefathiamidine, has been developed successfully in a fully aqueous medium. The present work may open up a novel opportunity for the production of cefathiamidine through a simple and green process.Graphical abstractEnzymatic synthesis of N-bromoacetyl-7-ACA, the key intermediate for the production of cefathiamidine, was reported for the first time. Electronic supplementary materialThe online version of this article (doi:10.1186/s40643-016-0127-3) contains supplementary material, which is available to authorized users.

The engineering and immobilization of penicillin G acylase onto thermo‐sensitive tri‐block copolymer system

“…The variation of L could be ascribed to the reaction rate, diffusion resistance, and steric resistance . Because immobilization reaction needed to overcome the activation energy, and the only way to realize this process was to pass through the energy accumulation, this process was time consuming; L increased with the prolongation of time naturally. Besides, due to the high viscosity of reaction system, molecules of PGA would need a relatively long time to diffuse to target spots.…”

“…For Ea and Ar, the variation of them could also be understood easily because the catalytic activity of PGA was seriously affected by pH, and the most suitable pH of PGA was 6 to 8. 38,39 Thus, if PGA was immobilized under acidic or alkaline environment, although large L could be obtained, the threedimensional space conformation of PGA had been changed, and the conformation of catalytic active center had been distorted, and Ea and Ar presented a low value naturally. Figure 4 showed the relationship among L, Ea, Ar, and concentration of PGA.…”

Immobilized penicillin G acylase with enhanced activity and stability using glutaraldehyde‐modified polydopamine‐coated Fe3O4 nanoparticles

“…For EA and EAR , the variation of them could be related to conformation of active site. The active site of PGA could be distorted under the harsh alkali or acidic conditions, so the most suitable pH of PGA was 8 39 . Thus, ELC could reach to large value in acidic or alkaline conditions, but the active site conformation of PGA had been distorted, EA and EAR reduced.…”

Shielding of Enzyme by a Stable and Protective Organosilica Layer on Monolithic Scaffolds for Continuous Bioconversion

“…Such a phenomenon might be caused by the no/partial coverage of enzyme by the organosilica layer, where enzymes were mainly exposed to the reaction medium during the reaction. As the reaction of PGAcatalyzed hydrolysis of PGK was an acid-producing process under the flow-through reaction mode, 29 enzymes not fully covered by organosilica would be prone to denature, due to the extremely acidic pH, or to detached from the support, due to the strong shearing force. Then, we examined the catalytic performance of the other two biocatalysts, PGA@PDA/ cordierite-H−OSi-9.5h and PGA@PDA/cordierite-H−OSi-15h.…”