Behaviour of α-aminoadipylcysteine and glutamylcysteine in the presence of intact and disrupted mycelium of a Cephalosporium sp

Abstract

1. δ-(l-α-Aminoadipyl)-l-cysteine, the corresponding d- and dl-α-aminoadipyl isomers, δ-(dl-α-amino[6−14C]adipyl)-l-cysteine and γ- and α-l-glutamyl-l-cysteine were synthesized. 2. The behaviour of δ-(l-aminoadipyl)-l-cysteine and the corresponding d- and dl-α-aminoadipyl isomers was studied in the presence of suspensions of intact mycelium of a Cephalosporium sp., suspensions treated ultrasonically and extracts obtained by grinding with alumina. 3. With intact mycelium the l-α-aminoadipyl isomer was removed more rapidly from the extracellular fluid than the corresponding d-isomer. 4. Addition of δ-(dl-α-amino[6−14C]adipyl)-l-cysteine to suspensions of intact mycelium led to the labelling of extracellular and intracellular penicillin N and cephalosporin C, but also to extensive hydrolysis of the dipeptide. 5. Broken-cell systems hydrolysed δ-(l-α-aminoadipyl)-l-cysteine and the corresponding d-α-aminoadipyl isomer, but the former was hydrolysed more readily than the latter. 6. γ- and α-l-Glutamyl-l-cysteine were also hydrolysed but δ-(l-α-aminoadipyl)-l-cysteinyl-l-valine was not. 7. Only part of the enzyme activity in broken-cell systems responsible for the hydrolysis of δ-(α-aminoadipyl)-l-cysteine was present in the supernatant obtained on centrifugation at 20000g. 8. Possible implications of these findings are discussed.