Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.24.3 (collagenase)
 18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The peptide substrate specificities of two matrix metalloproteinases (MMPs), interstitial collagenase (MMP-1), and 92-kDa gelatinase (MMP-9), have been examined. Starting with the parent substrate, Dnp-Pro-Leu-Gly approximately Leu-Trp-Ala-D-Arg-NH2, four separate substrate mixtures were synthesized at subsites P2(Leu) through P2'(Trp). These mixtures contained either naturally occurring L-amino acids, D-amino acids, or either of two distinct sets of miscellaneous amino acids. Combined, these mixtures gave 88 unique substitutions at each position and, over the four subsites, represented 352 potential substrates. Optimal substrates were identified using a combined high performance liquid chromatography/mass spectrometry analysis as previously reported. The results gave an extended profile of the substrate specificities for both MMP-1 and MMP-9 at subsites P2(Leu) through P2'(Trp). Using the data obtained from the mapping, a new peptide substrate, Dnp-Pro-Cha-Abu approximately Smc-His-Ala-D-Arg-NH2 (where Dnp is 2,4-dinitrophenyl, Cha is cyclohexylalanine, Abu is alpha-aminobutyric acid, and Smc is S-methylcysteine) was designed and characterized. This peptide showed a 36-fold improvement in turnover (kcat/Km) versus the parent substrate by interstitial collagenase. In addition, some collagenase subsite specificities described here were found to be different from those previously reported. Experimental data show that the observed selectivity is dependent on the original peptide template employed, which has broader implications for substrate specificity studies.
 ...
PMID:Characterization of the peptide substrate specificities of interstitial collagenase and 92-kDa gelatinase. Implications for substrate optimization. 780 5

The exchange of residues 67 and 205 of the S2 pocket of human cysteine cathepsins K and L induces a permutation of their substrate specificity toward fluorogenic peptide substrates. While the cathepsin L-like cathepsin K (Tyr67Leu/Leu205Ala) mutant has a marked preference for Phe, the Leu67Tyr/Ala205Leu cathepsin L variant shows an effective cathepsin K-like preference for Leu and Pro. A similar turnaround of inhibition was observed by using specific inhibitors of cathepsin K [1-(N-Benzyloxycarbonyl-leucyl)-5-(N-Boc-phenylalanyl-leucyl)carbohydrazide] and cathepsin L [N-(4-biphenylacetyl)-S-methylcysteine-(D)-Arg-Phe-beta-phenethylamide]. Molecular modeling studies indicated that mutations alter the character of both S2 and S3 subsites, while docking calculations were consistent with kinetics data. The cathepsin K-like cathepsin L was unable to mimic the collagen-degrading activity of cathepsin K against collagens I and II, DQ-collagens I and IV, and elastin-Congo Red. In summary, double mutations of the S2 pocket of cathepsins K (Y67L/L205A) and L (L67Y/A205L) induce a switch of their enzymatic specificity toward small selective inhibitors and peptidyl substrates, confirming the key role of residues 67 and 205. However, mutations in the S2 subsite pocket of cathepsin L alone without engineering of binding sites to chondroitin sulfate are not sufficient to generate a cathepsin K-like collagenase, emphasizing the pivotal role of the complex formation between glycosaminoglycans and cathepsin K for its unique collagenolytic activity.
 ...
PMID:The S2 subsites of cathepsins K and L and their contribution to collagen degradation. 1738 31