biostudies-literatureAdachi KNIDDK NIH HHSNHLBI NIH HHS137-44https://www.ebi.ac.uk/biostudies/studies/S-EPMC2636675biostudies-literatureUnknown481(2)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)bArchives of biochemistry and biophysicsRelationship between beta4 hydrogen bond and beta6 hydrophobic interactions during aggregate, fiber or crystal formation in oversaturated solutions of hemoglobin A and S.PMC2636675P60 HL038632-15S10002R01 DK061692U54 HL070596-050002U54 HL070596R01 HL069256R56 DK061692Surrey SAdachi KAsakura TDing MfalseRelationship between beta4 hydrogen bond and beta6 hydrophobic interactions during aggregate, fiber or crystal formation in oversaturated solutions of hemoglobin A and S.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)b2009-01-01T00:00:00Z2009 Jan2025-04-25T20:52:10.395Z2019-03-27T00:20:36ZS-EPMC26366751902221710.1016/j.abb.2008.11.006