Konomi T, Herchen S, Baldwin J E, Yoshida M, Hunt N A, Demain A L
Biochem J. 1979 Nov 15;184(2):427-30. doi: 10.1042/bj1840427.
Cell-free extracts of antibiotic-negative mutants of Cephalosporium acremonium converted delta-(L-alpha-aminoadipyl)-L-cysteinyl-D-valine (LLD-tripeptide) into an antibiotic that was destroyed by penicillinase. The enzymic activity of the extracts was destroyed by boiling, but was not inhibited by cycloheximide. LLL-Tripeptide was totally inactive as substrate. The product resembled isopenicillin N, but not penicillin N, in its antibacterial spectrum. We propose that isopenicillin N is the first product of cyclization of LLD-tripeptide.
顶头孢霉抗生素阴性突变体的无细胞提取物将δ-(L-α-氨基己二酰基)-L-半胱氨酰-D-缬氨酸(LLD-三肽)转化为一种能被青霉素酶破坏的抗生素。提取物的酶活性经煮沸后被破坏,但不受放线菌酮抑制。LLL-三肽作为底物完全无活性。该产物在抗菌谱上类似于异青霉素N,而非青霉素N。我们提出异青霉素N是LLD-三肽环化的首个产物。