Download MendeleySelective X-ray-induced NO photodissociation in haemoglobin crystals: evidence from a Raman-assisted crystallographic study.
Merlino, A., Fuchs, M.R., Pica, A., Balsamo, A., Dworkowski, F.S., Pompidor, G., Mazzarella, L., Vergara, A.(2013) Acta Crystallogr D Biol Crystallogr 69: 137-140
- PubMed: 23275172
- DOI: https://doi.org/10.1107/S0907444912042229
- Primary Citation of Related Structures:
4G51 - 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.
Organizational Affiliation:
Department of Chemical Sciences, University of Naples `Federico II', Italy.
