4G51

Crystallographic analysis of the interaction of nitric oxide with hemoglobin from Trematomus bernacchii in the T quaternary structure (fully ligated state).

Summary for 4G51

• Entry DOI: 10.2210/pdb4g51/pdb
• Descriptor: Hemoglobin subunit alpha, Hemoglobin subunit beta, NITRIC OXIDE, ... (5 entities in total)
• Functional Keywords: all alpha proteins, oxygen transporter, n-terminal acetylated serine, oxygen transport
• Biological source: Trematomus bernacchii (rockcod); More
• Total number of polymer chains: 4
• Total formula weight: 66259.25

Authors

Merlino, A.,Balsamo, A.,Pica, A.,Mazzarella, L.,Vergara, A. (deposition date: 2012-07-17, release date: 2013-01-16, Last modification date: 2024-11-06)

Primary citation

Merlino, A.,Fuchs, M.R.,Pica, A.,Balsamo, A.,Dworkowski, F.S.,Pompidor, G.,Mazzarella, L.,Vergara, A.
Selective X-ray-induced NO photodissociation in haemoglobin crystals: evidence from a Raman-assisted crystallographic study.
Acta Crystallogr.,Sect.D, 69:137-140, 2013

PubMed Abstract: Despite their high physiological relevance, haemoglobin crystal structures with NO bound to haem constitute less than 1% of the total ligated haemoglobins (Hbs) deposited in the Protein Data Bank. The major difficulty in obtaining NO-ligated Hbs is most likely to be related to the oxidative denitrosylation caused by the high reactivity of the nitrosylated species with O(2). Here, using Raman-assisted X-ray crystallography, it is shown that under X-ray exposure (at four different radiation doses) crystals of nitrosylated haemoglobin from Trematomus bernacchii undergo a transition, mainly in the β chains, that generates a pentacoordinate species owing to photodissociation of the Fe-NO bond. These data provide a physical explanation for the low number of nitrosylated Hb structures available in the literature.

PubMed: 23275172
DOI: 10.1107/S0907444912042229

Experimental method

X-RAY DIFFRACTION (2.5 Å)