Adenosyl homocysteinase (AHCY) (EC 3.3.1.1) or S-adenosyl homocysteine hydrolase (SAHH); is an enzyme that catalyzes the reversible hydrolysis of S-Adenosyl Homocysteine (SAH) to adenosine and homocysteine. Inhibition of AHCY results in the accumulation of SAH, a product inhibitor of S-adenosyl methionine (SAM)-dependent methyltransferases. AHCY is an important target as an antiviral and anticancer drug. Several characterized SAH inhibitors inhibit some DNA viruses (e.g. Pox viruses) and some negative stranded RNA viruses (e.g.: Marburg virus, Ebola virus & rabies). In BioVision's AHCY Inhibitor Screening kit the homocysteine generated from the breakdown of SAH is measured using a Thiol Detecting Reagent resulting in enhanced fluorescence w