A　72-kDa　matrix　metalloproteinase　(MMP;　sMP)　was　purified　from　silver　carp　skeletal　muscle　by　30-70%　ammonium　sulfate　fractionation　and　chromatography.　The　sMP　revealed　high　gelatinolytic　activity　from　30　to　60　degrees　C　and　showed　an　optimal　pH　of　8.0.　The　gelatin-hydrolyzing　activity　of　sMP　was　inhibited　by　ethylenediaminetetraacetic　acid　(EDTA),　dithiothreitol　(DTT),　L-Cys,　and　L-His.　Ca2+　enhanced　the　proteinase　activity,　while　a　higher　concentration　of　Zn2+　inhibited　this　activity.　Peptide　mass　fingerprinting　revealed　that　14　fragments　were　identical　to　MMP-2　from　grass　carp　(Ctenopharyngodon　idella).　The　full　length　of　the　cDNA　sequence　encoding　sMP　was　3005　bps,　with　an　open　reading　frame　(ORF)　of　1977　bps　encoding　658　amino　acid　residues.　Further,　sMP　could　effectively　hydrolyze　type　I　collagen　even　at　4　degrees　C;　its　activity　remained　steady　during　the　entire　storage　period　at　4　degrees　C.　These　results　indicated　that　sMP　is　MMP-2　and　may　have　been　involved　in　the　protein　degradation　of　fish　muscle　during　the　postmortem　stage.　(C)　2016　Elsevier　Ltd.　All　rights　reserved.