Analysis of MCP-3 cleavage by recombinant MMPs
| MMP . | kcat/Km(M−1s−1) . | Measured mass of MCP-3, d* . |
|---|---|---|
| MMP-1 | 2600 | 8574 |
| MMP-2 | 8000 | 8574 |
| MMP-3 | 2700 | 8574 |
| MMP-7 | 0 | 8935 |
| MMP-8 | 0 | 8935 |
| MMP-9 | 0 | 8935 |
| MMP-13 | 2600 | 8574 |
| MT1-MMP | 6000 | 8574 |
| Buffer control | 0 | 8935 |
| MMP . | kcat/Km(M−1s−1) . | Measured mass of MCP-3, d* . |
|---|---|---|
| MMP-1 | 2600 | 8574 |
| MMP-2 | 8000 | 8574 |
| MMP-3 | 2700 | 8574 |
| MMP-7 | 0 | 8935 |
| MMP-8 | 0 | 8935 |
| MMP-9 | 0 | 8935 |
| MMP-13 | 2600 | 8574 |
| MT1-MMP | 6000 | 8574 |
| Buffer control | 0 | 8935 |
Eight MMPs were assayed for their efficiency at processing MCP-3 after incubation for up to 18 hours at 37°C. For buffer control, chemokine in assay buffer was incubated in the absence of MMP for 18 hours at 37°C. Graphical analysis of time course reactions to monitor production of cleaved MCP-3 was used to estimate the kcat/Km values. Also shown is the mass of the reaction products as determined by electrospray ionization mass spectroscopy.
Mass of full-length (uncleaved) MCP-3 = 8935 d. A mass of 8574 d corresponds exactly to MCP-3(5-76) with a cleavage site at Gly4-Ile5.