Copper type II, ascorbate-dependent monooxygenases [1] are a class of enzymes that requires copper as a cofactor and which uses ascorbate as an electron donor. The enzymes which belong to this category are:

• Dopamine-β-monooxygenase (EC 1.14.17.1) (DBH) [2], which catalyzes the conversion of dopamine to the neurotransmitter norepinephrine.
• Peptidyl-glycine α-amidating monooxygenase (EC 1.14.17.3) (PAM), which catalyzes the conversion of the carboxy-terminal glycine of many active peptides and hormones to an amide group.

There are a few regions of sequence similarities between these two enzymes, two of these regions contain clusters of conserved histidine residues which are most probably involved in binding copper. We selected these two regions as signature patterns.