delta-(L-alpha-aminoadipyl)-L-cysteinyl-D-valine synthetase from Aspergillus nidulans. The first enzyme in penicillin biosynthesis is a multifunctional peptide synthetase.
J Biol Chem
; 264(7): 3680-4, 1989 Mar 05.
Article
em En
| MEDLINE
| ID: mdl-2645274
ABSTRACT
A multienzyme catalyzing the formation of delta-(L-alpha-aminoadipyl)-L-cysteinyl-D-valine, the first free intermediate in penicillin biosynthesis, was detected in an assay measuring the formation of tripeptide from L-[U-14C]valine in the presence of L-alpha-aminoadipic acid, L-cysteine, ATP, Mg2+ ions, and dithioerythritol. Enzyme was extracted from dry mycelium using a buffer with a high glycerol concentration and thiol protective agent to stabilize enzyme activity. In five steps the enzyme was purified 118-fold. It catalyzed ATP-pyrophosphate exchange in dependence of all three constituent amino acids, and the enzyme could be amino-acylated with L-[14C]valine. The molecular weight of the protein both native (in gel filtration chromatography) and denatured (polyacrylamide gel electrophoresis) was about 220 kDa. These data suggest that delta-(L-alpha-aminoadipyl)-L-cysteinyl-D-valine synthetase consists of a single polypeptide chain and a multienzyme thiotemplate mechanism for the reaction sequence is postulated.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oligopeptídeos
/
Penicilinas
/
Peptídeo Sintases
/
Aspergillus nidulans
Idioma:
En
Revista:
J Biol Chem
Ano de publicação:
1989
Tipo de documento:
Article