In this talk I will give an overview of our collaborative research programme into the enzyme dihydrodipicolinate synthase - a homotetrameric protein that catalyses the rate determining step of lysine biosynthesis and is an important antibiotic target.  Decades of research by several groups, including our own, have failed to design a potent inhibitor of this enzyme. However, our recent exploration of the evolution of the enzyme's quaternary architecture and its putative role in the enzyme's structure and function have opened up new avenues in drug design.