The human neutrophil lipocalin supports the allosteric activation of matrix metalloproteinases

摘要: The human neutrophil lipocalin (HNL), a member of the large family lipocalins that exhibit various physiological functions, is coexpressed in granulocytes with progelatinase B (MMP-9). Part it covalently bound to proenzyme and therefore may play possible role activation process promatrix metalloproteinases. We now report HNL able accelerate direct metalloproteinases slightly. A significant enhancement activity could be demonstrated for HgCl2- plasma kallikrein-induced all three secretory forms proMMP-9 proMMP-8. same activating effects were exerted by isolated from as well recombinant expressed yeast Pichia pastoris or Escherichia coli. This demonstrates carbohydrate moiety not essential biological HNL. Activation are obviously mediated entrapping remaining N-terminal sequence residues partially truncated into hydrophobic binding pocket In conclusion these results document can exert an enzyme-activating effect regulation inflammatory pathophysiological responses MMPs have been subject limited proteolytic processing.