The enzyme, characterized from the fruit fly Drosophila melanogaster, is a multi-domain oxidoreductase that acts as an F-actin disassembly factor. The enzyme selectively reduces two L-Met residues of F-actin, causing fragmentation of the filaments and preventing repolymerization . Free methionine is not a substrate . The reaction is stereospecific and generates the (R)-sulfoxide . In the absence of substrate, the enzyme can act as an NAD(P)H oxidase (EC 22.214.171.124) [4,5].