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.
Laboratorios de Biotecnología and Bioquímica. Antibióticos S.A., León. Spain.
J
J
Velasco
J
J
Luis Adrio
M
M
Angel Moreno
B
B
Díez
G
G
Soler
J L
JL
Barredo
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