Even if these substrates are not commercially available and
difficult to synthesize, they are essential to model the MMP
activity.Very recently, the importance of their thermal stability
on the activities of different MMP has been emphasized
and may help demonstrate subtle differences in their abilities
to hydrolyze triple helices [71]. Furthermore, the study indicating
that collagenase unwinds triple-helical collagen prior
to peptide bond hydrolysis, clearly supports the usefulness of
triple-helical peptides as MMPs substrates to understand the
mechanism of action of MMPs