6XD9 image
Entry Detail
PDB ID:
6XD9
Title:
Carbonmonoxy hemoglobin in complex with the antisickling agent 2-hydroxy-6-((6-(hydroxymethyl)pyridin-2-yl)methoxy)benzaldehyde (VZHE039)
Biological Source:
Source Organism:
PDB Version:
Deposition Date:
2020-06-10
Release Date:
2020-12-23
Method Details:
Experimental Method:
Resolution:
2.10 Å
R-Value Free:
0.25
R-Value Work:
0.19
R-Value Observed:
0.20
Space Group:
P 21 21 21
Macromolecular Entities
Polymer Type:polypeptide(L)
Description:Hemoglobin subunit alpha
Chain IDs:A, C
Chain Length:141
Number of Molecules:2
Biological Source:Homo sapiens
Polymer Type:polypeptide(L)
Description:Hemoglobin subunit beta
Chain IDs:B, D
Chain Length:146
Number of Molecules:2
Biological Source:Homo sapiens
Primary Citation
VZHE-039, a novel antisickling agent that prevents erythrocyte sickling under both hypoxic and anoxic conditions.
Sci Rep 10 20277 20277 (2020)
PMID: 33219275 DOI: 10.1038/s41598-020-77171-2

Abstact

Sickle cell disease (SCD) results from a hemoglobin (Hb) mutation βGlu6 → βVal6 that changes normal Hb (HbA) into sickle Hb (HbS). Under hypoxia, HbS polymerizes into rigid fibers, causing red blood cells (RBCs) to sickle; leading to numerous adverse pathological effects. The RBC sickling is made worse by the low oxygen (O2) affinity of HbS, due to elevated intra-RBC concentrations of the natural Hb effector, 2,3-diphosphoglycerate. This has prompted the development of Hb modifiers, such as aromatic aldehydes, with the intent of increasing Hb affinity for O2 with subsequent prevention of RBC sickling. One such molecule, Voxelotor was recently approved by U.S. FDA to treat SCD. Here we report results of a novel aromatic aldehyde, VZHE-039, that mimics both the O2-dependent and O2-independent antisickling properties of fetal hemoglobin. The latter mechanism of action-as elucidated through crystallographic and biological studies-is likely due to disruption of key intermolecular contacts necessary for stable HbS polymer formation. This dual antisickling mechanism, in addition to VZHE-039 metabolic stability, has translated into significantly enhanced and sustained pharmacologic activities. Finally, VZHE-039 showed no significant inhibition of several CYPs, demonstrated efficient RBC partitioning and high membrane permeability, and is not an efflux transporter (P-gp) substrate.

Legend

Protein

Chemical

Disease

Primary Citation of related structures