9Z8Q

Neurospora crassa polysaccharide monooxygenase 9D dose series - pseudohelix 3 (2.07 MGy)

Summary for 9Z8Q

• Entry DOI: 10.2210/pdb9z8q/pdb
• Related: 9Z8O 9Z8P
• Descriptor: Lytic polysaccharide monooxygenase NCU01050, beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, 2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, ... (9 entities in total)
• Functional Keywords: radiation damage, lpmo, photoreduction, polysaccharide monooxygenase, oxidoreductase
• Biological source: Neurospora crassa
• Total number of polymer chains: 2
• Total formula weight: 48508.98

Authors

Miller, S.A.,O'Dell, W.B.,Meilleur, F. (deposition date: 2025-11-18, release date: 2026-08-12)

Primary citation

Miller, S.A.,O'Dell, W.B.,Meilleur, F.
Dose-dependent structural and electron-density features in the lytic polysaccharide monooxygenase NcAA9D.
Acta Crystallogr D Struct Biol, 82:900-914, 2026

PubMed Abstract: Structural studies of copper-containing lytic polysaccharide monooxygenases (LPMOs) by X-ray crystallography are often complicated by radiation damage. In this study, we analyze a series of 36 X-ray crystal structures of NcAA9D, a Neurospora crassa AA9-family LPMO, determined from data collected at cryogenic temperature from a single crystal to investigate the progressive effects of radiation damage at the active site of this enzyme. We report new insights into the dose-dependence of active-site geometry in LPMOs and utilize the unique pre-bound dioxygen site of NcAA9D to analyze the impact of X-ray dose on the electron density of this species. It is well established that photoreduction of the LPMO active-site copper(II) leads to expulsion of its water ligands. We further characterize this displacement and the corresponding electron-density smearing, a phenomenon that can lead to the erroneous modeling of copper-bound dioxygen species. These findings suggest that radiation-dose series collected from a single crystal provide invaluable data to support unambiguous assignment of radiation-sensitive intermediates at the active site of LPMOs and other radiation-sensitive redox enzymes.

PubMed: 42517195
DOI: 10.1107/S205979832600639X

Experimental method

X-RAY DIFFRACTION (1.1 Å)