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Updated: Aug 21, 2026

Characterization of Glycoproteins with the Immunoglobulin Fold by X-Ray Crystallography and Biophysical Techniques
08:58

Characterization of Glycoproteins with the Immunoglobulin Fold by X-Ray Crystallography and Biophysical Techniques

Published on: July 5, 2018

Crystallization mechanisms of hemoglobin C in the R state

Angela R Feeling-Taylor1, S-T Yau, Dimiter N Petsev

  • 1Department of Anatomy and Structural Biology, Albert Einstein College of Medicine and Montefiore Hospital, Comprehensive Sickle Cell Center, The Bronx, New York, USA.

Biophysical Journal
|September 30, 2004
PubMed

Insights

Hemoglobin C (HbC) crystallization in red blood cells offers insights into condensation diseases. HbC crystals grow by single molecule attachment, not strand alignment, suggesting shared mechanisms with other protein crystallizations.

Area of Science:

  • Biophysics
  • Molecular Biology
  • Hematology

Background:

  • Hemoglobin C (HbC) crystallization within red blood cells is implicated in sickle cell disease variants (HbSC and HbCC).
  • Understanding HbC crystallization mechanisms can illuminate broader condensation disease pathologies.

Purpose of the Study:

  • To investigate the molecular mechanisms of HbC crystallization using atomic force microscopy.
  • To elucidate the growth process of HbC crystals in high-concentration phosphate buffer.

Main Methods:

  • High-resolution atomic force microscopy (AFM) was employed to observe HbC crystallization.
  • Experiments were conducted using the stable carbomonoxy form of HbC in phosphate buffer.

Main Results:

  • HbC crystal surfaces exhibit reconstruction into four-molecule-wide strands at equilibrium.
  • Crystal growth occurs via the addition of single molecules to step edges, not preformed strand alignment.
  • Step propagation velocity during growth is dependent on the crystallization driving force.

Conclusions:

  • HbC crystallization mechanisms are analogous to those observed in other protein crystallization systems.
  • In vitro protein crystallization strategies may be transferable to understanding and potentially treating condensation diseases.

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