Biochemical Characterization and Crystal Structure of a Novel NAD-Dependent Isocitrate Dehydrogenase from .

The marine diatom originated from a series of secondary symbiotic events and has been used as a model organism for studying diatom biology. A novel type II homodimeric isocitrate dehydrogenase from (PtIDH1) was expressed, purified, and identified in detail through enzymatic characterization. Kinetic analysis showed that PtIDH1 is NAD-dependent and has no detectable activity with NADP.