Photoinduced Nitric Oxide Exchange in the Diazeniumdiolate Siderophore, Pandorachelin.

TitlePhotoinduced Nitric Oxide Exchange in the Diazeniumdiolate Siderophore, Pandorachelin.
Publication TypeJournal Article
Year of Publication2025
AuthorsSusman M, Makris C, Butler A
JournalACS Chem Biol
Date Published2025 Sep 02
ISSN1554-8937
Abstract

C-diazeniumdiolate siderophores are a small class of photoactive bacterial Fe(III) chelators. Driven by genome mining, we discovered a new C-type diazeniumdiolate siderophore, pandorachelin, produced by the rhizospheric bacterium, Pandoraea norimbergensis DSM 11628. The biosynthetic gene cluster encoding the production of pandorachelin is conserved across several species. are environmentally widespread and are increasingly prevalent clinical pathogens, spurring new interest in their metabolites. UV irradiation photolytically cleaves the N-N bonds within the diazeniumdiolate-containing graminine constituents of pandorachelin. With EPR spin trapping, we directly detect nitric oxide released from the two C-diazeniumdiolate ligands of pandorachelin upon UV irradiation. Additionally, we show that nitric oxide can react with the intermediates during the photoreaction to reconstruct the diazeniumdiolate groups via exchange of the distal nitric oxide (NO) and thereby recover Fe(III)-binding capacity. The photochemistry of this class of siderophores points to a broader biological role, both in their propensity to release the biological signaling molecule, nitric oxide, and in their ability to undergo photoinduced NO exchange.

DOI10.1021/acschembio.5c00484
Alternate JournalACS Chem Biol
PubMed ID40897679