9HTT

McCP in complex with photocaged nitric oxide, 1.44 s, 0.19 microjoule, SSX

Summary for 9HTT

• Entry DOI: 10.2210/pdb9htt/pdb
• Descriptor: Cytochrome c, HEME C, ZINC ION, ... (5 entities in total)
• Functional Keywords: mccp, heme, gas binding, metal binding protein
• Biological source: Methylococcus capsulatus str. Bath
• Total number of polymer chains: 2
• Total formula weight: 36103.73

Authors

Smyth, P.,Williams, L.J.,Hough, M.A.,Worrall, J.A.R.,Owen, R.L. (deposition date: 2024-12-19, release date: 2025-09-03, Last modification date: 2025-09-10)

Primary citation

Smyth, P.,Jaho, S.,Williams, L.J.,Karras, G.,Fitzpatrick, A.,Thompson, A.J.,Battah, S.,Axford, D.,Horrell, S.,Lucic, M.,Ishihara, K.,Kataoka, M.,Matsuura, H.,Shimba, K.,Tono, K.,Tosha, T.,Sugimoto, H.,Owada, S.,Hough, M.A.,Worrall, J.A.R.,Owen, R.L.
Time-resolved serial synchrotron and serial femtosecond crystallography of heme proteins using photocaged nitric oxide.
Iucrj, 12:582-594, 2025

PubMed Abstract: Time-resolved X-ray crystallography is undergoing a renaissance due to the development of serial crystallography at synchrotron and XFEL beamlines. Crucial to such experiments are efficient and effective methods for uniformly initiating time-dependent processes within microcrystals, such as ligand binding, enzymatic reactions or signalling. A widely applicable approach is the use of photocaged substrates, where the photocage is soaked into the crystal in advance and then activated using a laser pulse to provide uniform initiation of the reaction throughout the crystal. This work characterizes photocage release of nitric oxide and binding of this ligand to two heme protein systems, cytochrome c'-β and dye-decolourizing peroxidase B using a fixed target sample delivery system. Laser parameters for photoactivation are systematically explored, and time-resolved structures over timescales ranging from 100 µs to 1.4 s using synchrotron and XFEL beamlines are described. The effective use of this photocage for time-resolved crystallography is demonstrated and appropriate illumination conditions for such experiments are determined.

PubMed: 40843530
DOI: 10.1107/S2052252525006645

Experimental method

X-RAY DIFFRACTION (1.75 Å)