Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.24.23 (MMP)
 4,246 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A small uterine metalloproteinase of the rat has been shown by amino acid and cDNA sequencing to be orthologous to human pump-1. Both proteinases are now designated as matrilysin or matrix metalloproteinase 7. The properties of purified uterine metalloproteinase and recombinant pump-1 were compared. Their specificities on substrates (gelatins, fibronectin, transferrin, elastin, Azocoll, and (7-methoxycoumarin-4-yl)acetyl-Pro-Leu-Gly-Leu-(3,[2, 4-dinitrophenyl]-L-2, 3-diaminopropionyl)-Ala-Arg-NH2) are similar and distinct from those of the stromelysins and gelatinases. The two matrilysins have similar sensitivity to hydroxamate and pseudopeptide inhibitors. Rat matrilysin selectively cleaves the alpha 2(I) chain of rat gelatin, producing major cuts at Gly713-decreases-Ile714, Gly775-decreases-Leu776, and Gly809-decreases-Ile810. Rat matrilysin produces maximum activation of latent human interstitial collagenase 1 (pro-matrix metalloproteinase 1) when added in the presence of 4-aminophenylmercuric acetate (APMA) by cleaving the Gln80-decreases-Phe81 bond. Rat and human matrilysin do not directly activate latent rat collagenase 3 (matrix metalloproteinase 13) and do not enhance its activation when added together with APMA. Autoactivation of collagenase 3 in the presence of APMA results in cleavage at Val81-decreases-Tyr82 corresponding to the Gln80-decreases-Phe81 cleavage in collagenase 1. Thus collagenase 3 is capable of maximal autoactivation, whereas collagenase 1 is dependent upon another matrix metalloproteinase in order to be activated to its full potential.
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PMID:Characterization of rat uterine matrilysin and its cDNA. Relationship to human pump-1 and activation of procollagenases. 760 62

Human matrix metalloproteinase-7 (MMP-7 = matrilysin) was overproduced in Escherichia coli as a recombinant zymogen (31 kDa), the C-terminus of which bears artificial hexa-histidines. Most of the enzyme was isolated from the insoluble fraction of the cell lysate and purified by a single step using Ni-NTA resin after solubilization of the precipitates with 8 M urea solution. The resin-bound recombinant protein was refolded into a form that is activatable by p-amino-phenylmercuric acetate in an autocatalytic manner. The activated enzyme cleaved a synthetic peptide substrate at the reported site for MMP-7. Digestion of carboxymethylated transferrin (a natural substrate of MMP-7) by the recombinant proteinase generated fragments with the same peptide map as in the case of native purified MMP-7. The autocatalytic activation and enzyme reaction were entirely dependent on the presence of calcium and zinc ions. The enzyme activity to cleave carboxymethylated transferrin was inhibited by tissue inhibitors of metalloproteinases-1 and -2, MMP-specific inhibitors. The activity of the recombinant MMP-7 was also inhibited by a synthetic peptide derived from a part of the cysteine switch that maintains the zymogen in an inactive state. Thus, we report here a simple means of preparing a large quantity of recombinant proMMP-7 that can be used to study the activation mechanism and to screen synthetic inhibitors.
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PMID:Purification and refolding of recombinant human proMMP-7 (pro-matrilysin) expressed in Escherichia coli and its characterization. 874 67

Membrane type 3 matrix metalloproteinase (MT3-MMP), an activator for the zymogen of MMP-2 (proMMP-2, or progelatinase A), is known to be expressed in human placenta, brain, lung and rat vascular smooth muscle cells, but information about its biochemical properties is limited. In the present study, we expressed and purified a truncated form of MT3-MMP lacking the transmembrane and intracytoplasmic domain (DeltaMT3) and characterized the enzyme biochemically. DeltaMT3 digested type III collagen into characteristic 3/4- and 1/4-fragments by cleaving the Gly781-Ile782 and Gly784-Ile785 bonds of alpha1(III) chains. Although DeltaMT3 did not have such an activity against type I collagen, it attacked the Gly4-Ile5 bond of the triple helical portion of alpha2(I) chains, leading to removal of the crosslink containing N-terminal telopeptides. By quantitative analyses of the activities of DeltaMT3 and a similar deletion mutant of MT1-MMP (DeltaMT1), DeltaMT3 was approximately fivefold more efficient at cleaving type III collagen. DeltaMT3 also digested cartilage proteoglycan, gelatin, fibronectin, vitronectin, laminin-1, alpha1-proteinase inhibitor and alpha2-macroglobulin into almost identical fragments to those given by DeltaMT1, although carboxymethylated transferrin digestion by DeltaMT3 generated some extra fragments. The activity of DeltaMT3 was inhibited by tissue inhibitor of metalloproteinases-2 (TIMP-2) and TIMP-3 in a 1 : 1 stoichiometry, but not by TIMP-1. ProMMP-2 was partially activated by DeltaMT3 to give the intermediate form. These results indicate that, like MT1-MMP, MT3-MMP exhibits proteolytic activities against a wide range of extracellular matrix molecules. However, differences in the proMMP-2 activation and tissue distribution suggest that MT3-MMP and MT1-MMP play different roles in the pathophysiological digestion of extracellular matrix.
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PMID:Characterization of a truncated recombinant form of human membrane type 3 matrix metalloproteinase. 1041 55

Unlike the gelatinases (MMP-2 and -9), matrilysin (MMP-7) and collagenases (MMP-1 and -13) are difficult to detect at low levels in conventional casein or gelatin zymography. In this report, heparin was used to enhance the zymographic assays for MMP-7, -1, and -13. With the addition of heparin to the enzyme sample, MMP-7 can be detected at a level of 30 pg in transferrin zymography and MMP-1 and -13 can be detected at a level of 0.2 ng in gelatin zymography. Carboxymethylated transferrin is used instead of casein as a substrate for assaying rat MMP-7. This substrate does not require a prerun step or substrate cross-linking to give uniform staining and clear band formation. It is necessary for heparin to run to the same region of the gel as the enzyme to produce its enhancing effect. For MMP-7 movement of heparin and enzyme is almost equal; for the collagenases it is necessary to add heparin to each well after the electrophoretic run is underway. Possible mechanisms of activity enhancement are discussed.
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PMID:Heparin-enhanced zymographic detection of matrilysin and collagenases. 1137 76

Matrix metalloproteinase-7 (MMP-7) (also known as matrilysin-1) is secreted as a proenzyme (proMMP-7) and plays a key role in the degradation of various extracellular matrix (ECM) and non-ECM molecules after activation. To identify the binding proteins related to proMMP-7 activation, a human lung cDNA library was screened by yeast two-hybrid system using proMMP-7 as bait. We identified a candidate molecule CD151, which is a member of the transmembrane 4 superfamily. Complex formation of proMMP-7 with CD151 was demonstrated by immunoprecipitation of the molecules from CaR-1 cells, a human rectal carcinoma cell line, expressing both proMMP-7 and CD151, and CD151 stable transfectants incubated with proMMP-7. Yeast two-hybrid assays using deletion mutants of proMMP-7 and CD151 suggested an interaction between the propeptide of proMMP-7 and the COOH-terminal extracellular loop of CD151. The binding activity of (125)I-labeled proMMP-7 to CD151 on the cell membranes was shown with CD151 stable transfectants. Laser-scanning confocal microscopy demonstrated that proMMP-7 colocalizes with CD151 on the cell membranes of CD151 stable transfectants and CaR-1 cells. In situ zymography using crosslinked carboxymethylated transferrin, a substrate of MMP-7, demonstrated proteinase activity on and around CD151 stable transfectants and CaR-1 cells, while the activity was abolished by their treatment with MMP inhibitors, anti-MMP-7 antibody or anti-CD151 antibody. In human lung adenocarcinoma tissues, colocalization of MMP-7 and CD151 was demonstrated on the carcinoma cells. Metalloproteinase activity was present in these tissues and could be inhibited by antibodies to MMP-7 or CD151. These data demonstrate for the first time that proMMP-7 is captured and activated on the cell membranes through interaction with CD151, and suggest the possibility that similar to the MT1-MMP/MMP-2 system, MMP-7 is involved in the pericellular activation mechanism mediated by CD151, a crucial step in proteolysis on the cell membranes under various pathophysiological conditions including cancer invasion and metastasis.
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PMID:Pericellular activation of proMMP-7 (promatrilysin-1) through interaction with CD151. 1620 75

Human ADAM12 (a disintegrin and metalloproteinase) is a multidomain zinc metalloproteinase expressed at high levels during development and in human tumors. ADAM12 exists as two splice variants: a classical type 1 membrane-anchored form (ADAM12-L) and a secreted splice variant (ADAM12-S) consisting of pro, catalytic, disintegrin, cysteine-rich, and EGF domains. Here we present a novel activity of recombinant ADAM12-S and its domain deletion mutants on S-carboxymethylated transferrin (Cm-Tf). Cleavage of Cm-Tf occurred at multiple sites, and N-terminal sequencing showed that the enzyme exhibits restricted specificity but a consensus sequence could not be defined as its subsite requirements are promiscuous. Kinetic analysis revealed that the noncatalytic C-terminal domains are important regulators of Cm-Tf activity and that ADAM12-PC consisting of the pro domain and catalytic domain is the most active on this substrate. It was also observed that NaCl inhibits ADAM12. Among the tissue inhibitors of metalloproteinases (TIMP) examined, the N-terminal domain of TIMP-3 (N-TIMP-3) inhibits ADAM12-S and ADAM12-PC with low nanomolar Ki(app) values while TIMP-2 inhibits them with a slightly lower affinity (9-44 nM). However, TIMP-1 is a much weaker inhibitor. N-TIMP-3 variants that lack MMP inhibitory activity but retained the ability to inhibit ADAM17/TACE failed to inhibit ADAM12. These results indicate unique enzymatic properties of ADAM12 among the members of the ADAM family of metalloproteinases.
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PMID:Catalytic properties of ADAM12 and its domain deletion mutants. 1808 11