8HCI

Crystal structure of a holoenzyme Fe-free TglHI for Pseudomonas syringae Peptidyl (S) 2-mercaptoglycine biosynthesis

Summary for 8HCI

• Entry DOI: 10.2210/pdb8hci/pdb
• Descriptor: RiPP Recognition protein, DUF692 family protein (3 entities in total)
• Functional Keywords: biosynthesis, complex, fe binding protein, peptide binding protein, biosynthetic protein
• Biological source: Pseudomonas syringae pv. maculicola str. ES4326; More
• Total number of polymer chains: 4
• Total formula weight: 131508.88

Authors

Cheng, W.,Zheng, Y.H.,Fu, X.L. (deposition date: 2022-11-01, release date: 2023-08-23, Last modification date: 2023-10-25)

Primary citation

Zheng, Y.,Xu, X.,Fu, X.,Zhou, X.,Dou, C.,Yu, Y.,Yan, W.,Yang, J.,Xiao, M.,van der Donk, W.A.,Zhu, X.,Cheng, W.
Structures of the holoenzyme TglHI required for 3-thiaglutamate biosynthesis.
Structure, 31:1220-1232.e5, 2023

PubMed Abstract: Structural diverse natural products like ribosomally synthesized and posttranslationally modified peptides (RiPPs) display a wide range of biological activities. Currently, the mechanism of an uncommon reaction step during the biosynthesis of 3-thiaglutamate (3-thiaGlu) is poorly understood. The removal of the β-carbon from the Cys in the TglA-Cys peptide catalyzed by the TglHI holoenzyme remains elusive. Here, we present three crystal structures of TglHI complexes with and without bound iron, which reveal that the catalytic pocket is formed by the interaction of TglH-TglI and that its activation is conformation dependent. Biochemical assays suggest a minimum of two iron ions in the active cluster, and we identify the position of a third iron site. Collectively, our study offers insights into the activation and catalysis mechanisms of the non-heme dioxygen-dependent holoenzyme TglHI. Additionally, it highlights the evolutionary and structural conservation in the DUF692 family of biosynthetic enzymes that produce diverse RiPPs.

PubMed: 37652001
DOI: 10.1016/j.str.2023.08.004

Experimental method

X-RAY DIFFRACTION (3.399 Å)