Structure-function relationship of adenosylhomocysteinase as a target for drug design

We realized that the studies on AHCYL which had been reported as adenosylhomocysteinase-like protein was useful to execute this project, since the protein is a natural mutant of the enzyme. Although it is reported that the protein had no catalytic activity of adenosylhomocysteinase, more detailed study is needed from the enzymological point of view. As a result of precise comparison of the primary structures, it became clear that the four catalytic residues and the main residues related to the coenzyme binding, all of which we had solved, were conserved in the protein. As an initial step, we established an expression system in the E. coli, purified the protein, and started protein-chemical and enzymological analysis. From the several lines of experimental evidence, we proposed a unique structure that seems to reflect the function of AHCYL.