3P5Q

Ferric R-state human aquomethemoglobin

Summary for 3P5Q

• Entry DOI: 10.2210/pdb3p5q/pdb
• Descriptor: Hemoglobin subunit alpha, Hemoglobin subunit beta, PROTOPORPHYRIN IX CONTAINING FE, ... (5 entities in total)
• Functional Keywords: r-state, ferric, human aquomethemoglobin, oxygen transport
• Biological source: Homo sapiens (human); More
• Total number of polymer chains: 2
• Total formula weight: 32549.94

Authors

Yi, J.,Thomas, L.M.,Richter-Addo, G.B. (deposition date: 2010-10-10, release date: 2011-06-08, Last modification date: 2023-09-06)

Primary citation

Yi, J.,Thomas, L.M.,Richter-Addo, G.B.
Structure of human R-state aquomethemoglobin at 2.0 A resolution
Acta Crystallogr.,Sect.F, 67:647-651, 2011

PubMed Abstract: The crystal structure of tetrameric (αβ)(2) R-state human adult aquomethemoglobin is reported at 2.0 Å resolution. The asymmetric unit contained one αβ subunit pair. The R-state crystal belonged to space group P4(1)2(1)2, with unit-cell parameters a = b = 53.6, c = 192.8 Å. An Fe-bound water molecule was modeled into the heme distal pockets of each of the α and β subunits. In the α subunit, a highly ordered liganded water was modeled with an Fe-O(water) distance of 2.2 Å and appears to be protected against escape from the distal pocket by the conformation of the heme propionate groups, which point upwards towards the distal His58 residue aided by a hydrogen-bonding network involving the solvent. In the β subunit, the liganded water exhibited greater motion and was modeled with a longer Fe-O(water) distance of 2.5 Å; in this subunit both propionate groups point downwards away from the distal His63 residue, presumably allowing greater motion of the liganded water in and out of the distal pocket.

PubMed: 21636902
DOI: 10.1107/S1744309111012528

Experimental method

X-RAY DIFFRACTION (2 Å)