Type I collagen from sea cucumber (Stichopus japonicus) and the role of matrix metalloproteinase-2 in autolysis

Abstract Autolysis is a major issue affecting the quality of sea cucumber during transportation and processing. To further clarify the mechanism, characteristics of type I collagen from sea cucumber Stichopus japonicas and its degradation by recombinant matrix metalloproteinase-2 (rMMP-2) were investigated. Scanning electron microscopic (SEM) images showed that the body wall of fresh sea cucumber with intact collagen fibrils was disaggregated after autolysis. Pepsin-soluble collagen of Stichopus japonicas (SjPSC) was prepared and its filamentous feature was observed using SEM. Circular dichroism spectrum analysis showed that SjPSC had native triple helix structure and its denaturation temperature was 34.0°C using differential scanning calorimeter. The α chain gene of SjPSC encoding 1400 amino acid residues was cloned. A polyclonal antibody against SjPSC was prepared and was used to detect collagen degradation during autolysis. The effect of rMMP-2 on the body wall strongly suggested that MMP-2 had an important role in sea cucumber autolysis by disaggregating collagen fibres into fibrils.