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.