MD and QM/MM study on catalytic mechanism of a FAD-dependent enzyme ORF36: For nitro sugar biosynthesis

- A phenylalanine/leucine residue pair is important for FAD binding.
- Three elementary catalytic steps were found.
- Hydroxylation step is the rate-determining step.
- Oxygen atom that comes from the coenzyme FADHOOH stays in the product.
- Of all the residues, Ser162 suppresses the hydroxylation reaction most.