9OQU

N-hydroxylamine dehydratase (NohD) T98A/K167A mutant crystal structure with heme and N-hydroxylated ornithine (5h soak)

9OQU の概要

• エントリーDOI: 10.2210/pdb9oqu/pdb
• 分子名称: N-hydroxylamine dehydratase (NohD), PROTOPORPHYRIN IX CONTAINING FE, N~5~-hydroxy-L-ornithine, ... (4 entities in total)
• 機能のキーワード: dehydratase, piperazate synthase, heme, n-n bond, hydroxylamine, biosynthetic protein
• 由来する生物種: Actinomadura luzonensis
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 46305.56

構造登録者

Higgins, M.A.,Shi, X.,Hoffarth, E.R.,Du, Y.L.,Ryan, K.S. (登録日: 2025-05-21, 公開日: 2025-12-03)

主引用文献

Higgins, M.A.,Mirotadze, N.,Shi, X.,Hoffarth, E.R.,Du, Y.L.,Ryan, K.S.
Conversion of a Heme-Dependent Dehydratase to a Piperazate Synthase Reveals the Role of the Heme Propionate Group in N-N Bond-Formation.
J.Am.Chem.Soc., 147:39160-39168, 2025

PubMed Abstract: Enzymes that form nitrogen-nitrogen bonds are employed in natural product biosynthesis and the nitrogen cycle. Piperazate synthase forms the cyclic hydrazine l-piperazic acid from l--OH-ornithine, using heme as a cofactor. In this work, we discover sequence-related enzyme NohD that instead reacts with l--OH-ornithine to release ammonia, and we solve its structure to 1.4 Å resolution. We then employ structure-guided site-directed mutagenesis to endow variants of NohD with piperazate synthase activity. Crystal structures of the NohD variants reveal how the heme propionate changes conformation, positioning it upward toward the amino nitrogen, where it is likely to activate the amine for N-N bond-formation. This study highlights a key structural requirement for N-N bond-formation and sets the stage for the development of new N-N-bond-forming catalysts.

PubMed: 41101755
DOI: 10.1021/jacs.5c08886

実験手法

X-RAY DIFFRACTION (1.73 Å)