A retroprotein has exactly the same sequence as a naturally-occurring protein, except that the direction in which the polypeptide backbone runs through the protein is exactly the opposite of what it was in the first place. In this paper, we create and express a gene in which the sequence of occurrence of amino acids along the polypeptide chain of Hsp12.6 from Caenorhabditis elegans is subjected to a retro-transformation to create retro-Hsp12.6, which is a homolog of the heat shock domain of the human lens protein, alpha crystallin, a protein which associates through extensive homo-multimerization into spherical hollow assemblies to function as a molecular chaperone. Retro-Hsp12.6 happened to fold and assemble into hollow spherical assemblies, with numerous interesting features. We could not establish the actual atomic structure as only plate-like crystals of the protein could be obtained in one crystallization trial. However, the fact that retro-Hsp12.6 folded and was stable was significant.

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