Agarose-vinyl sulfone (VS) beads have proven to be a good support immobilize several enzymes. However, some enzymes are hardly immobilized on it. This is the case of penicillin G acylase (PGA) from Escherichia coli, which very slowly this (less than 10% in 24 h). enzyme also not significantly adsorbed aminated MANAE-agarose beads, an anionic exchanger. In study, were modified with divinyl (DVS)...

A specific acylase designated A933 acylase was isolated and purified to 90% protein homogeneity from Streptomyces fulvoviridis A933 17M9 which produces PS-5, epithienamycins A and C and MM 17880 together with minor carbapenem analogs, penicillin N and cephamycin C. This enzyme was found to catalyze the depantothenylation of OA-6129 carbapenems; the acyl exchange of OA-6129 carbapenems with acyl...

Covalently immobilised penicillin G acylase (PGA-450) accepts in toluene, at controlled water activity (aw), a broad range of amino compounds as nucleophiles in kinetically controlled acylation. Hydrolytic reactions were prevented and complete conversions were achieved in short times even when working with an equimolar concentration of the substrates. The recovery of the products was facile, le...

AlkL is an outer membrane porin from Pseudomonas. Its expression in E. coli was shown to greatly stimulate the oxidation of hydrophobic substrates by a a recombinant oxygenase enzyme system. Bacterial membranes can be perturbed for biotechnological purposes by enzymatic treatment. Some of the enzymes and their actions are discussed on this commercial site. Different chemical treatments that are...

The production of penicillin G acylase (PGA, an important industrial enzyme) from a wild strain of Bacillus megaterium using a pool of free amino acids as substrate was studied in a bench-scale bioreactor. Experiments carried out in shakers showed that the substitution of casein for free amino acids in the presence of cheese whey was the culture medium that provided the highest productivity. Se...

Cephalexin (CEX) was synthesized with 7-amino-3-deacetoxycephalosporanic acid (7-ADCA) and D(–)-phenylglycine methyl ester (PGME) using immobilized penicillin G acylase from Escherichia coli. It was found that substrate concentration and in situ product could remarkably influence the ratio of synthesis to hydrolysis (S/H) and the efficiency of CEX synthesis. The optimal ratio of enzyme to subst...

The objective of this work was to study enzyme immobilization on chitosan activated with glutaraldehyde, aiming to produce a cheap biocatalyst. Two different immobilization strategies were studied: one-point and multipoint covalent attachment to the solid matrix. The multipoint covalent attachment derivative had an 82% immobilization yield. It was 4.9-fold more stable than the free enzyme at 50...

The constraint in synthesis of ß-lactams by penicillin acylase is the hydrolysis of the activated acyl donor and the synthetic product. The thermodynamically controlled synthesis of ß-lactams deals with direct acylation of a nucleophile (6APA, 7-ACA or 7-ADCA) by free acids in acidic pH and high concentration of solvent to achieve good yield. On the other hand, the kinetically controlled synthe...