Open AccessDeacetoxycephalosporin C synthase isozymes exhibit diverse catalytic activity and substrate specificity
Author(s) -
Chin Hong Soon,
Sim Janet,
Seah Keng Ing,
Sim Tiow Suan
Publication year - 2003
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2003.tb11525.x
Subject(s) - streptomyces clavuligerus , biochemistry , enzyme , streptomyces , isozyme , chemistry , stereochemistry , carbenicillin , biology , bacteria , ampicillin , antibiotics , clavulanic acid , genetics , amoxicillin
The biosynthesis of cephalosporins involving a thiozolidine ring expansion is catalyzed by deacetoxycephalosporin C synthase (DAOCS). In this study, three DAOCS isozymes were cloned and expressed as active enzymes together with Streptomyces jumonjinensis DAOCS that was newly isolated and partially characterized. The enzymes showed excellent substrate conversion for penicillin G, phenethicillin, ampicillin and carbenicillin, but they were less effective in the ring expansion of penicillin V, amoxicillin and metampicillin. Streptomyces clavuligerus DAOCS was the most active among the recombinant enzymes. The results also showed that truncation of 20 amino acids at the C‐terminus of the Acremonium chrysogenum deacetoxy/deacetylcephalosporin C synthase polypeptide did not affect penicillin ring expansion.