1bij
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CROSSLINKED, DEOXY HUMAN HEMOGLOBIN A
OverviewOverview
The crystal structure of human hemoglobin crosslinked between the, Lysbeta82 residues has been determined at 2.30 A resolution. The, crosslinking reaction was performed under oxy conditions using bis(3, 5-dibromosalicyl) fumarate; the modified hemoglobin has increased oxygen, affinity and lacks cooperativity. Since the crystallization occurred under, deoxy conditions, the resulting structure displays conformational, characteristics of both the (oxy) R and the (deoxy) T-states. beta82XLHbA, does not fully reach its T-state conformation due to the presence of the, crosslink. The R-state-like characteristics of deoxy beta82XLHbA include, the position of the distal Hisbeta63 (E7) residue, indicating a possible, reason for the high oxygen affinity of this derivative. Other areas of the, molecule, particularly those thought to be important in the allosteric, transition, such as Tyrbeta145 (HC2) and the switch region involving, Proalpha(1)44 (CD2), Thralpha(1)41 (C6) and Hisbeta(2)97 (FG4), are in, intermediate positions between the R and T-states. Thus, the structure may, represent a stabilized intermediate in the allosteric transition of, hemoglobin.
About this StructureAbout this Structure
1BIJ is a Protein complex structure of sequences from Homo sapiens with HEM and 2FU as ligands. Full crystallographic information is available from OCA.
ReferenceReference
Crystal structure of Lysbeta(1)82-Lysbeta(2)82 crosslinked hemoglobin: a possible allosteric intermediate., Fernandez EJ, Abad-Zapatero C, Olsen KW, J Mol Biol. 2000 Mar 10;296(5):1245-56. PMID:10698631
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