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2d5x
From Proteopedia
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Crystal structure of carbonmonoxy horse hemoglobin complexed with L35
Overview
Although detailed crystal structures of haemoglobin (Hb) provide a clear, understanding of the basic allosteric mechanism of the protein, and how, this in turn controls oxygen affinity, recent experiments with artificial, effector molecules have shown a far greater control of oxygen binding than, with natural heterotropic effectors. Contrary to the established text-book, view, these non-physiological compounds are able to reduce oxygen affinity, very strongly without switching the protein to the T (tense) state. In an, earlier paper we showed that bezafibrate (BZF) binds to a surface pocket, on the alpha subunits of R state Hb, strongly reducing the oxygen affinity, of this protein conformation. Here we report the crystallisation of Hb, with L35, a related compound, and show that this binds to the central, cavity of both R and T state Hb. The mechanism by which L35 reduces oxygen, affinity is discussed, in relation to spectroscopic studies of effector, binding.
About this Structure
2D5X is a Protein complex structure of sequences from Equus caballus with HEM, CMO and L35 as ligands. Full crystallographic information is available from OCA.
Reference
R-state haemoglobin with low oxygen affinity: crystal structures of deoxy human and carbonmonoxy horse haemoglobin bound to the effector molecule L35., Yokoyama T, Neya S, Tsuneshige A, Yonetani T, Park SY, Tame JR, J Mol Biol. 2006 Feb 24;356(3):790-801. Epub 2005 Dec 21. PMID:16403522
Page seeded by OCA on Thu Nov 8 13:29:13 2007
Categories: Equus caballus | Protein complex | Neya, S. | Park, S.Y. | Tame, J.R. | Tsuneshige, A. | Yokoyama, T. | Yonetani, T. | CMO | HEM | L35 | Allosteric effector | Crystal structure | Hemoglobin
