8VYC

Graspetide pre-fuscimiditide A1C/T3C variant

Summary for 8VYC

• Entry DOI: 10.2210/pdb8vyc/pdb
• NMR Information: BMRB: 31145
• Descriptor: ATP-grasp target RiPP (1 entity in total)
• Functional Keywords: graspetide, omega-ester peptide, ripp, cyclic peptide, unknown function
• Biological source: Thermobifida fusca YX
• Total number of polymer chains: 1
• Total formula weight: 2416.69

Authors

Link, A.J.,Choi, B. (deposition date: 2024-02-08, release date: 2024-05-08, Last modification date: 2024-05-15)

Primary citation

Choi, B.,Acuna, A.,Link, A.J.
Cyclic Peptides from Graspetide Biosynthesis and Native Chemical Ligation.
J.Am.Chem.Soc., 146:11605-11609, 2024

PubMed Abstract: The ribosomally synthesized and post-translationally modified peptide (RiPP) superfamily of natural products includes many examples of cyclic peptides with diverse macrocyclization chemistries. The graspetides, one family of macrocyclized RiPPs, harbor side chain-side chain ester or amide linkages. We recently reported the structure and biosynthesis of the graspetide pre-fuscimiditide, a 22-amino-acid (aa) peptide with two ester cross-links forming a stem-loop structure. These cross-links are introduced by a single graspetide synthetase, the ATP-grasp enzyme ThfB. Here we show that ThfB can also catalyze the formation of amide or thioester cross-links in prefuscimiditide, with thioester formation being especially efficient. We further show that upon proteolysis to reveal an N-terminal cysteine residue, the thioester-linked peptide rapidly and quantitatively rearranges via native chemical ligation into an isopeptide-bonded head-to-tail cyclic peptide. The solution structure of this rearranged peptide was determined by using 2D NMR spectroscopy experiments. Our methodology offers a straightforward recombinant route to head-to-tail cyclic peptides.

PubMed: 38634647
DOI: 10.1021/jacs.4c02745

Experimental method

SOLUTION NMR