On the stability of sickle hemoglobin macrofibers: isolated layers of antiparallel double strands

Abstract

Sickle hemoglobin macrofibers consist of rows of antiparallel double strands twisted about the particle axis. Under appropriate conditions the outer two rows can dissociate from the particle. These structures retain the helical twist of the parent macrofiber and slowly dissociate to monomers over a period of several hours. Individual double strands or pairs of parallel double strands are never observed, suggesting that only the antiparallel pairing is energetically favorable.