Relationship between beta4 hydrogen bond and beta6 hydrophobic interactions during aggregate, fiber or crystal formation in oversaturated solutions of hemoglobin A and S.

ABSTRACT: Oversaturated deoxy-alpha(2)beta(2)(T4V) aggregated instantly without a delay time, which is in contrast to the delay time before the generation of fibers of deoxy-HbS and deoxy-alpha(2)beta(2)(E6V,D73H). Solubility of deoxy-alpha(2)beta(2)(T4V) was approximately 10-fold lower than that of deoxy-HbS and was similar to oxy- and deoxy-alpha(2)beta(2)(E6V,T4V). These results indicate that beta4Val in HbA in the oxy and deoxy forms with or without beta6Val facilitates hydrophobic interaction of the A-helix with the EF helix of adjacent molecules without forming a beta4/beta73 hydrogen bond. Deoxy-HbA generated crystals following aggregation as does HbC-Harlem(alpha(2)beta(2)(E6V,D73N)), while alpha(2)beta(2)(T4V) and alpha(2)beta(2)(D73H) as well as HbS, alpha(2)beta(2)(E6V,D73H) and alpha(2)b

SUBMITTER: Adachi K 

PROVIDER: S-EPMC2636675 | biostudies-literature | 2009 Jan

REPOSITORIES: biostudies-literature