Figure 5.

Effects of different concentration of Ca²⁺ ions on MMP-12 activity. The MMP-12 assay was based on the MMP-12 hydrolysis of FRET substrate ( AnaSpec, Inc, Fremont, CA,USA) .A total of 100 μl reaction mixture consisting of 1 μl (100 ng) MMP-12, different concentrations of Ca²⁺ ions (0-40 mM) and 50 μl of buffer ( AnaSpec, Inc, Fremont, CA,USA)were incubated at 37°C for 10 min. Fluorescence was read at Ex/Em wavelengths = 340 nm/490 nm for 60 min. RFU: Relative Fluorescence Unit.