The loss of all deuterium labels from previous feedings of [2-²H]-,
[3,3-²H₂]-, and [2,3,3-²H₃]arginines had indicated the possible intermediacy
of β-hydroxy- and β-ketoarginine (30 and 31, respectively) in the
biosynthesis of the streptolidine portion of streptothricin F (la).
In order to confirm or refute this evidence, D,L-[2,3,3,5,5-²H₅]-
arginine (32) was...
Feeding of [3-¹³C, 2-¹⁵N]arginine, 38a, unequivocally established that the β-
arginine moiety of blasticidin S, 1, was formed from α-arginine by an intramolecular
migration of the α-amino group to the β- position. Further feedings using chirally
deuteriated arginines 38e and 38f revealed that the aminomutase process occurred with
inversion of...
Early studies on the biosynthesis of Sarubicin A, 1, had suggested the
intermediacy of the novel aromatic amino acid 6-hydroxyanthranilic acid,
17. To investigate the biosynthetic steps beyond 17, [¹³C-¹⁵N carboxamide]
6-hydroxyanthranilamide, 27a, was synthesized, and fed to fermentations
of Streptomyces helicus. Incorporation of 27a into 1 provided suggestive
evidence...