2ZLX
Horse methemoglobin high salt, pH 7.0 (66% relative humidity)
Summary for 2ZLX
| Entry DOI | 10.2210/pdb2zlx/pdb |
| Related | 1jy7 1lfl 1lfq 1y8h 1y8i 1y8k 2ZLT 2ZLU 2ZLV 2ZLW |
| Descriptor | Hemoglobin subunit alpha, Hemoglobin subunit beta, PROTOPORPHYRIN IX CONTAINING FE (3 entities in total) |
| Functional Keywords | protein hydration, allosteric transitions, variability in quaternary structure, solvent content and crystal structure, water-mediated transformation, heme, iron, metal-binding, oxygen transport, polymorphism, transport, oxygen storage |
| Biological source | Equus caballus (Horse) More |
| Total number of polymer chains | 4 |
| Total formula weight | 64807.06 |
| Authors | Kaushal, P.S.,Sankaranarayanan, R.,Vijayan, M. (deposition date: 2008-04-10, release date: 2008-06-24, Last modification date: 2023-11-01) |
| Primary citation | Kaushal, P.S.,Sankaranarayanan, R.,Vijayan, M. Water-mediated variability in the structure of relaxed-state haemoglobin Acta Crystallogr.,Sect.F, 64:463-469, 2008 Cited by PubMed Abstract: The crystal structure of high-salt horse methaemoglobin has been determined at environmental relative humidities (r.h.) of 88, 79, 75 and 66%. The molecule is in the R state in the native and the r.h. 88% crystals. At r.h. 79%, the water content of the crystal is reduced and the molecule appears to move towards the R2 state. The crystals undergo a water-mediated transformation involving a doubling of one of the unit-cell parameters and an increase in water content when the environmental humidity is further reduced to r.h. 75%. The water content is now similar to that in the native crystals and the molecules are in the R state. The crystal structure at r.h. 66% is similar, but not identical, to that at r.h. 75%, but the solvent content is substantially reduced and the molecules have a quaternary structure that is in between those corresponding to the R and R2 states. Thus, variation in hydration leads to variation in the quaternary structure. Furthermore, partial dehydration appears to shift the structure from the R state to the R2 state. This observation is in agreement with the earlier conclusion that the changes in protein structure that accompany partial dehydration are similar to those that occur during protein action. PubMed: 18540052DOI: 10.1107/S1744309108013109 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (2.8 Å) |
Structure validation
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