Environmentally safe production of 7-aminodeacetoxycephalosporanic acid (7-ADCA) using recombinant strains of Acremonium chrysogenum.
Medically useful semisynthetic cephalosporins are made from 7-aminodeacetoxycephalosporanic acid (7-ADCA) or 7-aminocephalosporanic acid (7-ACA). Here we describe a new industrially amenable bioprocess for the production of the important intermediate 7-ADCA that can replace the expensive and environmentally unfriendly chemical method classically used. The method is based on the disruption and one-step replacement of the cefEF gene, encoding the bifunctional expandase/hydroxylase activity, of an actual industrial cephalosporin C production strain of Acremonium chrysogenum. Subsequent cloning and expression of the cefE gene from Streptomyces clavuligerus in A. chrysogenum yield recombinant strains producing high titers of deacetoxycephalosporin C (DAOC). Production level of DAOC is nearly equivalent (75-80%) to the total beta-lactams biosynthesized by the parental overproducing strain. DAOC deacylation is carried out by two final enzymatic bioconversions catalyzed by D-amino acid oxidase (DAO) and glutaryl acylase (GLA) yielding 7-ADCA. In contrast to the data reported for recombinant strains of Penicillium chrysogenum expressing ring expansion activity, no detectable contamination with other cephalosporin intermediates occurred.
Velasco
J
J
Laboratorios de Biotecnología and Bioquímica. Antibióticos S.A., León. Spain.
Luis Adrio
J
J
Angel Moreno
M
M
Díez
B
B
Soler
G
G
Barredo
J L
JL
D000164:Acremonium / Q000235:genetics / Q000378:metabolism*; D002511:Cephalosporins / Q000096:biosynthesis*; D002851:Chromatography, High Pressure Liquid; D005285:Fermentation; D005800:Genes, Fungal; D013058:Mass Spectrometry; D010957:Plasmids; D011995:Recombination, Genetic
D002511:Cephalosporins; C014320:7-aminodesacetoxycephalosporanic acid