Application 5′-deoxyadenosine (5′dADO) is a substrate of bacterial methylthioadenosine/S-adenosylhomocysteine (MTA/SAH) nucleosidase and a product inhibitor produced by radical SAM enzymes. 5′-dADO may be useful to study the specificity and distribution of radical S-adenosyl-L-methionine enzymes.