Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Allosteric intermediates indicate R2 is the liganded hemoglobin end state

M A Schumacher1, E E Zheleznova, K S Poundstone

  • 1Department of Biochemistry and Molecular Biology, Oregon Health Sciences University, 3181 SW Sam Jackson Park Road, Portland, OR 97201-3098, USA.

Proceedings of the National Academy of Sciences of the United States of America
|July 22, 1997
PubMed
Summary

Chemically crosslinked hemoglobins reveal novel intermediate conformations. These findings support an allosteric pathway involving the R2 state, highlighting its physiological significance.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Intravenous tranexamic acid and lower limb arthroplasty-a randomised controlled feasibility study.

Anaesthesia and intensive care·2018
Same author

Biocompatibility and immunogenicity of elastin-like recombinamer biomaterials in mouse models.

Journal of biomedical materials research. Part A·2017
Same author

Comparison of preoperative and intraoperative assessment of aortic stenosis severity by echocardiography.

British journal of anaesthesia·2017
Same author

Minimally invasive cardiac output monitoring: agreement of oesophageal Doppler, LiDCOrapid™ and Vigileo FloTrac™ monitors in non-cardiac surgery.

Anaesthesia and intensive care·2016
Same author

Measurement of peak aortic jet velocity in the perioperative period-machine variability: implications for assessment of aortic stenosis severity.

Anaesthesia and intensive care·2015
Same author

The relationship between superior vena cava diameter and collapsibility and central venous pressure.

Anaesthesia and intensive care·2015

Area of Science:

  • Protein structure and dynamics
  • Biochemistry and molecular biology
  • Allosteric regulation mechanisms

Background:

  • Hemoglobin allostery is a classic model for protein conformational changes.
  • Understanding hemoglobin's quaternary structure transitions is crucial for deciphering its function.
  • Previous models proposed T-R and R-R2 allosteric pathways.

Purpose of the Study:

  • To elucidate the allosteric pathway of hemoglobin using chemically crosslinked variants.
  • To investigate the structural basis of hemoglobin's conformational states.
  • To assess the physiological relevance of the R2 conformation.

Main Methods:

  • X-ray crystallography was used to determine the structures of two chemically crosslinked, fully liganded hemoglobins.

Related Experiment Videos

  • High-resolution structural data (2.3 A and 2.6 A) were obtained for alpha2beta82CA82beta and alpha2beta82ND82beta hemoglobins.
  • Comparative structural analysis was performed to identify intermediate conformations.

    • Main Results:

    • The crosslinked hemoglobins adopted intermediate conformations distinct from the canonical R and T states.
    • These intermediate structures were found to lie between the R and R2 states, not R and T.
    • The observed conformations provide direct structural evidence for the R2 state's role.

    Conclusions:

    • The study supports an allosteric pathway involving T -> R -> R2 transitions in hemoglobin.
    • The findings underscore the physiological importance of the R2 conformation in hemoglobin function.
    • This work refines our understanding of protein allostery using hemoglobin as a model system.