Deuterolysin (, Penicillium roqueforti protease II, microbial neutral proteinase II, acid metalloproteinase, neutral proteinase II, Penicillium roqueforti metalloproteinase) is an enzyme. This enzyme catalyses the following chemical reaction
This enzyme is present in Penicillium roqueforti, P. caseicolum, Pyricularia oryzae, Aspergillus sojae and A. oryzae.