is normally abbreviated DXR, but it is sometimes named IspC. This enzyme is responsible for terpenoid biosynthesis in some organisms . [ 1 ] In Arabidopsis thaliana 1-deoxy-D-xylulose 5-phosphate reductoisomerase is the first committed enzyme of the non-mevalonate pathway for isoprenoid biosynthesis. The enzyme requires Mn2+ , Co2+ or Mg2+ for