Allosteric intermediates indicate R2 is the liganded hemoglobin end state.
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ABSTRACT:
SUBMITTER: Schumacher MA
PROVIDER: S-EPMC21516 | biostudies-literature | 1997 Jul
REPOSITORIES: biostudies-literature
Publications
Allosteric intermediates indicate R2 is the liganded hemoglobin end state.
Schumacher M A MA Zheleznova E E EE Poundstone K S KS Kluger R R Jones R T RT Brennan R G RG
Proceedings of the National Academy of Sciences of the United States of America 19970701 15
Hemoglobin has been a long-standing paradigm for understanding protein allostery. Here, the x-ray structures of two chemically crosslinked, fully liganded hemoglobins, alpha2beta82CA82beta and alpha2beta82ND82beta, are described at 2.3 A and 2.6 A resolution, respectively. Strikingly, these crosslinked hemoglobins assume intermediate conformations that lie between those of R and the controversial liganded hemoglobin state R2 rather than between R and T. Thus, these structures support only a T le ...[more]
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