enzyme in the chain of mitochondrial P450 systems that synthesize steroid hormones. Enzymes that use NADP(H) as a substrate In 2018 and 2019, the first two reports of enzymes that catalyze the removal of the 2' phosphate of NADP(H) in eukaryotes emerged. First the cytoplasmic protein MESH1 (), then the mitochondrial protein nocturnin were reported. Of note, the structures and NADPH binding of MESH1 (5VXA) and nocturnin (6NF0) are not related. References Nucleotides Coenzymes Pyridinium compounds