2025/05/22 by Yannasittha Jiramongkol, Karishma Patel, Jason Johansen‐Leete +7 · 1 voice · 1 citation
Biochemistry, Genetics and Molecular Biology · Medicine · #Adenosine and Purinergic Signaling #Aldose Reductase and Taurine #Peptidase Inhibition and Analysis
paper · pdf · doi:10.1038/s41467-025-59960-3
openalex publication_date 2025/05/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/23
-dependent stability of proteins bearing an N-terminal cysteine residue through the N-degron pathway. Despite their important role in hypoxic adaptation, which renders them potential therapeutic and agrichemical targets, structural information on NCO substrate binding remains elusive. To overcome this challenge, we employed a unique strategy by which a cyclic peptide inhibitor of the mammalian NCO, 2-aminoethanethiol dioxygenase (ADO), was identified by mRNA display and used as a scaffold to graft substrate moieties. This allowed the determination of two substrate analogue-bound crystal structures of ADO. Key binding interactions were revealed, including bidentate coordination of the N-terminal residue at the metal cofactor. Subsequent structure guided mutagenesis identified aspartate-206 as an essential catalytic residue, playing a role in reactive oxygen intermediate orientation or stabilisation. These findings provide fundamental information on ADO substrate interactions, which can elucidate enzyme mechanism and act as a platform for chemical discovery.