The molecular mass of the purified P. panacis peptidase was determined to be approximately 49 kDa by SDS-PAGE ( Fig. 2). Several authors have reported that peptidases from Pseudomonas spp. have molecular masses between 45 and 52 kDa. Extracellular peptidases of this molecular mass produced by Pseudomonas spp. are often designated in literature as AprX or AprA metallopeptidases. These peptidases belong to the epralysins, a subfamily of the serralysin family of metallopeptidases (Clan MA) (Takahashi, 2013).