Related Experiment Video
Updated: Jun 17, 2026

An Efficient Method for the Synthesis of Peptoids with Mixed Lysine-type/Arginine-type Monomers and Evaluation of Their Anti-leishmanial Activity
Published on: November 2, 2016
Dapdiamides, tripeptide antibiotics formed by unconventional amide ligases
Jessica Dawlaty1, Xiaorong Zhang, Michael A Fischbach
1Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA.
Abstract:
Construction of a genomic DNA library from Pantoea agglomerans strain CU0119 and screening against the plant pathogen Erwinia amylovora yielded a new family of antibiotics, dapdiamides A-E (1-5). The structures were established through 2D-NMR experiments and mass spectrometry, as well as the synthesis of dapdiamide A (1). Transposon mutagenesis of the active cosmid allowed identification of the biosynthetic gene cluster. The dapdiamide family's promiscuous biosynthetic pathway contains two unconventional amide ligases that are predicted to couple its constituent monomers.
Related Concept Videos
Inhibitors of Gram-positive Cell Wall Synthesis
Peptidoglycan Synthesis
Preparation of Amides
The DCC-promoted synthesis of amides begins with the protonation of DCC by carboxylic acid. The protonation makes it a better acceptor. Next, the addition of carboxylate to the protonated carbodiimide gives a reactive acylating agent.
Subsequently, the amine acts as a nucleophile that attacks the acylating agent to form a tetrahedral intermediate. In the...
Peptide Bonds
Aryldiazonium Salts to Azo Dyes: Diazo Coupling
Inhibitors of Bacterial Protein Synthesis

