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1.
Type IV collagenase (gelatinase) has a marked substrate specificity for denatured collagen (gelatin). Cleavage site specificity of type IV collagenase from human skin was determined using small collagenous peptides with varied sequences around Gly-Leu or Gly-Ile. Type IV collagenase showed essentially the same order of preference for the peptide substrates as did interstitial collagenase. Both required a peptide with a minimum of six amino acid residues to demonstrate significant gelatinolytic activity and were able to cleave uncharged molecules more rapidly than charged molecules. the repeating Gly-X-Y-Gly sequence of collagen is not an absolute requirement for either enzyme since both digested AcPro-Leu-Gly-Ile-Leu-Ala-Ala-OC2H5 at 70% of the rate of the best substrate peptide, AcPro-Leu-Gly-Leu-Leu-Gly-OC2H5. Km and kcat (Vmax) values were determined for several of the peptides and for the native substrate. Turnover numbers with type IV collagenase were similar to those with interstitial collagenase (Weingarten, H., Martin, R., and Feder, J. (1985) Biochemistry 24, 6730-6734). However, the Km for all peptides investigated was approximately 10-fold lower for type IV collagenase than for interstitial collagenase. Because type IV collagenase does not cleave helical interstitial collagens, the data support the conclusion that secondary structure determines whether the peptide bond can be hydrolyzed at any potential cleavage site.  相似文献   

2.
The ability of various peptides cleaved by plasmin from human fibrinogen and fibronectin or fibrinogen- and fibronectin- related synthetic peptides to induce histamine release from mast cells and collagenase and elastase from PMN-leukocytes was examined. Low molecular weight fibrinogen degradation products showed dose dependent secretion of collagenase. These peptides (mol. wt. 1.4 kD) at the concentration of 10(-5) M released about 47% of collagenase and 13% of elastase. Synthetic fibrinopeptides A and B had a similar strong collagenase releasing potency and also released histamine from mast cells. Peptides from plasmin digestion of fibronectin containing cell attachment site with sequence Arg-Gly-Asp-Ser and also synthetic peptide reproducing this amino-acid sequence at the concentration of 1000 micrograms/ml released about 50% of collagenase and 55% of elastase from PMN-leukocytes. Moreover peptides containing cell attachment and gelatin binding site induced histamine release from mast cells. The association of fibrinogen and fibronectin degradation with activation of mast cells may motivate the treatment with antihistaminic drugs of all pathological conditions where the intensive protein degradation takes place.  相似文献   

3.
The primary structure of the Hypoderma lineatum collagenase was determined. Chymotrypsin digestion and thermolysin fragmentation of the chymotryptic core gave 30 and 5 peptides, respectively, accounting for all the residues of the protein. These peptides were aligned with overlapping peptides derived from tryptic and Staphylococcus aureus V8 proteinase digests. Hypoderma collagenase is a serine proteinase composed of 230 amino acids (Mr 25,223). It displays a high degree of sequential homology with the serine proteinases of the trypsin family, especially with another collagenolytic enzyme, the proteinase I of the crab Uca pugilator. The six half-cystinyl residues of Hypoderma collagenase correspond to 6 of the 10 half-cystinyl residues of chymotrypsin, and the residues forming the charge-relay system of the active site of chymotrypsin (His-57, Asp-102, and Ser-195) are found in corresponding regions. The prediction of the secondary structure of the collagenase is given.  相似文献   

4.
The position of 3-hydroxyproline was investigated in the triplet sequences of peptides released by collagenase digestion of a collagen preparation from kidney cortex. Composition of the collagen preparation indicated that it was largely or wholly of basement membrane origin. 3-Hydroxyproline was detected in only one sequence, the tripeptide, glycyl-3-hydroxyprolyl-4-hydroxyproline, which accounted for a major fraction of the total 3-hydroxyproline obtained in the peptides released by collagenase. Preliminary data, based on sequencing the peptide mixture released by collagenase treatment, suggested that, in contrast, 4-hydroxyproline occurs predominantly if not exclusively in the Y position of Gly-X-Y triplet sequences in the collagen preparation studied.  相似文献   

5.
To understand the role of Ca(2+) in vertebrate in the structure and action of collagenase, we have examined peptides that interact with recombinant human fibroblast collagenase for their affinities towards Ca(2+) and Zn(2+) in a non-polar solvent. Two of the peptides, GPQGIAGQ and GNVGLAGA, had sequences in collagen which are, respectively, cleaved and not cleaved by collagenase. A third peptide, PSYFLNAG, had a collagenase-cleaved sequence in ovostatin, a globular protein substrate. Peptides TVGCEECTV and CLPREPGL were derived from TIMP-1; the former competitively inhibits collagenase while the latter does not. The relative rates of hydrolysis of the peptides by collagenase had the order GPQGIAGQ>PSYFLNAG>GNVGLAGA. Circular dichroism spectral data in trifluoroethanol showed that while the TIMP control peptide, CLPREPGL, bound only Zn(2+), the other four peptides bound both Ca(2+) and Zn(2+) with definite stoichiometries. Ca(2+) could displace Zn(2+) in the substrate peptides while Zn(2+) displaced Ca(2+) in the TIMP peptide. GPQGIAGQ, PSYFLNAG and TVGCEECTV formed peptide:Ca(2+):Zn(2+) ternary complexes. Our results suggest that both collagen and globular protein substrates of collagenase may bind Ca(2+) and Zn(2+) in the enzyme's active site. This, in turn, may account for the known importance of the non-catalytic Ca(2+) and Zn(2+) in collagenase activity.  相似文献   

6.
Rat testicular cells in culture produce several metalloproteinases including type IV collagenases (Sang et al. Biol Reprod 1990; 43:946-955, 956-964). We have now investigated the regulation of testicular cell type IV collagenase and other metalloproteinases in vitro. Soluble laminin stimulated Sertoli cell type IV collagenase mRNA levels. However, three peptides corresponding to different domains of the laminin molecule (CSRAKQAASIKVASADR, FALRGDNP, CLQDGDVRV) did not influence type IV collagenase mRNA levels. Zymographic analysis of medium collected from these cultures revealed that neither soluble laminin nor any of the peptides influenced 72-kDa type IV collagenase protein levels. However, peptide FALRGDNP resulted in both, a selective increase in two higher molecular-weight metalloproteinases (83 kDa and 110 kDa and in an activation of the 72-kDa rat type IV collagenase. Interleukin-1, phorbol ester, testosterone, and FSH did not affect collagenase activation. Immunocytochemical studies demonstrated that the addition of soluble laminin resulted in a redistribution of type IV collagenase from intracellular vesicles to the cell-substrate region beneath the cells. Peptide FALRGDNP induced a change from a vesicular to peripheral plasma membrane type of staining pattern. Zymography of plasma membrane preparations demonstrated triton-soluble gelatinases of 76 kDa, 83 kDa, and 110 kDa and a triton-insoluble gelatinase of 225 kDa. These results indicate that testicular cell type IV collagenase mRNA levels, enzyme activation, and distribution are influenced by laminin and RGD-containing peptides.  相似文献   

7.
A specific collagenase (EC 3.4.24.3) has been found and purified from serum-free culture medium of 11095 epidermoid carcinoma of rat prostate. The molecular weight of this collagenase was estimated at 71 000 and the pH optimum was approx. 7. At 26 degrees C, the collagenase cleaved collagen at a site 3/4 the length from the N-terminus. At 37 degrees C, this collagenase degraded collagen to smaller peptides. The enzyme activity was inhibited by serum, cysteine and EDTA, but not by protease inhibitors. The presence of collagenase in rat tumor tissue suggests that this enzyme might play a significant role in tissue invasion by cancer cells.  相似文献   

8.
The action of purified rheumatoid synovial collagenase and human neutrophil elastase on the cartilage collagen types II, IX, X and XI was examined. At 25 degrees C, collagenase attacked type II and type X (45-kDa pepsin-solubilized) collagens to produce specific products reflecting one and at least two cleavages respectively. At 35 degrees C, collagenase completely degraded the type II collagen molecule to small peptides whereas a large fragment of the type X molecule was resistant to further degradation. In contrast, collagen type IX (native, intact and pepsin-solubilized type M) and collagen type XI were resistant to collagenase attack at both 25 degrees C and 35 degrees C even in the presence of excess enzyme. Mixtures of type II collagen with equimolar amounts of either type IX or XI did not affect the rate at which the former was degraded by collagenase at 25 degrees C. Purified neutrophil elastase, shown to be functionally active against soluble type III collagen, had no effect on collagen type II at 25 degrees C or 35 degrees C. At 25 degrees C collagen types IX (pepsin-solubilized type M) and XI were also resistant to elastase, but at 35 degrees C both were susceptible to degradation with type IX being reduced to very small peptides. Collagen type X (45-kDa pepsin-solubilized) was susceptible to elastase attack at 25 degrees C and 35 degrees C as judged by the production of specific products that corresponded closely with those produced by collagenase. Although synovial collagenase failed to degrade collagen types IX and XI, all the cartilage collagen species examined were degraded at 35 degrees C by conditioned culture medium from IL1-activated human articular chondrocytes. Thus chondrocytes have the potential to catabolise each cartilage collagen species, but the specificity and number of the chondrocyte-derived collagenase(s) has yet to be resolved.  相似文献   

9.
Destruction of cartilage by matrix metalloproteinases (MMPs) plays a significant role in the pathology of osteoarthritis (OA). A translatable biomarker of MMP activity would enable development of MMP inhibitors for the treatment of OA and potentially the improved diagnosis of OA. A directed approach to identifying specific MMP cleavage products as potential biomarkers has been undertaken. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to identify peptides generated by MMP-driven degradation of human articular cartilage (HAC) in vivo. It was shown that a 45-mer peptide fragment of collagen type II with five hydroxyprolines (OH) can be selectively produced by the activity of collagenase, an enzyme purported to be involved in the pathology of OA. This 45-mer is the most abundant neoepitope peptide found in biological fluids such as urine and synovial fluid. An immunoaffinity LC-MS/MS assay has been developed to quantify collagen type II neoepitope peptides as biomarkers of collagenase modulation. The lower limit of quantification for this assay was established to be 0.035 nM. The assay was used to measure the levels of collagen type II peptides in the urine of both clinical (healthy human subjects) and preclinical species. The urinary levels of the most abundant peptides are reported for rat, rabbit, guinea pig, dog, and healthy human adult subjects. The utility of this peptide to monitor collagenase activity in vivo has been demonstrated through its detailed characterization in HAC explants as well as in the urine of human and other preclinical species.  相似文献   

10.
L abadie , J. 1990. Synthesis of collagenase by the phytopathogenic bacterium Corynebacterium rathayii. Journal of Applied Bacteriology 69 , 828–833.
The collagenase-producing bacterium tentatively called Empedobacter collagenolyti-cum was recently identified as Corynebacterium rathayii . Production of collagenase was studied in different media containing peptones or peptides of known sequences. A hexapeptide, Pro-Ala-Gly-Pro-Pro-Gly, is an inducer almost as good as collagen.  相似文献   

11.
Significant levels of collagenase activity have been found in extracts of isolated rat hepatocytes, but not in extracts of rat liver. Hepatocytes prepared by perfusion of liver with 125I-clostridial collagenase and washed repeatedly retained significant amounts of the radiolabeled proteases. During the first 24–48 hours of primary culture of the hepatocytes, the contaminating clostridial collagenase was rapidly inactivated and degraded as judged first, by loss of collagenase activity from both cell extracts and culture medium; and second, by release of 125I into the medium largely in the form of iodinated small peptides.  相似文献   

12.
Polymeric collagen fibrils have been reacted with fluorescein and rhodamine isothiocyanates to produce fluorescent dye-labelled fibrils, containing seven dye substituents per molecule of tropocollagen within the polymeric collagen fibrils. Two dye-labelled peptides per molecule of tropocollagen were solubilised by trypsin (EC 3.4.21.4) from the telopeptide regions and four dye-labelled peptides were located in the helical regions solubilised by bacterial collagenase (EC 3.4.24.3). The solubilisation of dye-labelled peptides from these insoluble substrates were employed to measure the kinetics of trypsin and collagenase digestion of the telopeptide and helical regions, respectively, of the insoluble polymeric collagen fibrils. These studies demonstrated an apparent excess of enzyme for the readily available substrate under conditions when it was known that a vast excess of substrate existed in the reaction mixture calculated in terms of a molecular ratio. A point of equivalence was established for both trypsin and bacterial collagenase, approximately one enzyme molecule per 870 substrate molecules. On either side of this point the quantity of products formed was controlled by either the enzyme concentration or the substrate concentration. The results can be explained in terms of the inaccessibility of tropocollagen molecules within the molecular architecture of the polymeric collagen fibrils. The external layer of tropocollagen molecules obstruct collagenolytic enzymes penetrating to, and forming enzyme-substrate complexes with, the bulk of the substrate within the interior of the fibrils.  相似文献   

13.
The hydrolysis of the model collagenase substrate, 2,4-dinitrophenyl-Pro-Gln-Gly-Ile-Ala-Gly-Gln- -Arg by partially purified tadpole back-skin collagenase was monitored by separation of the substrate peptide from the product peptides 2,4-dinitrophenyl-Pro-Gln-Gly and Ile-Ala-Gly-Gln- -Arg by reverse-phase high-performance liquid chromatography. The method provides a sensitive, relatively rapid means of determination of collagenase activity using purified enzyme samples. It is not by itself, however, suitable for use with impure systems since the tissue culture medium from tadpole back skin was found to contain at least three peptidases which could be separated by gel filtration and which showed identical high-performance liquid chromatographic elution profiles using the octapeptide model substrate, but only one of which cleaved triple helical collagen.  相似文献   

14.
We have identified and sequenced a cDNA encoding human neutrophil collagenase from a lambda gt11 cDNA library constructed from mRNA extracted from the peripheral leukocytes of a patient with chronic granulocytic leukemia. The library was screened with an oligonucleotide probe constructed from the putative zinc-binding region of fibroblast collagenase. Eleven positive clones were identified, of which the one bearing the largest insert (2.2 kilobases (kb)) was sequenced. From the nucleotide sequence of the 2.2-kb cDNA clone we have deduced a 467-amino acid sequence representing the entire coding sequence of the enzyme. The deduced protein was confirmed as neutrophil collagenase by conformity with the amino-terminal sequence analyses of three tryptic peptides of purified neutrophil collagenase. The cDNA clone hybridizes to a 3.3-kb mRNA present in RNA extracted from human bone marrow but did not hybridize with RNA isolated from U937 cells induced to differentiate with phorbol myristate acetate. Neutrophil collagenase was found to possess 57% identity with the deduced protein sequence for fibroblast collagenase with 72% chemical similarity. Certain regions of the molecule, including the putative zinc-binding region, are highly conserved. When compared with the published sequence for fibroblast collagenase, neutrophil collagenase contains four additional sites for glycosylation. Medium from COS-7 cells transfected with a pcDNA1 eucaryotic expression vector containing cDNA for neutrophil collagenase degraded type I collagen into the three-quarter, one-quarter fragments characteristic of mammalian interstitial collagenase activity. Thus, definitive evidence based on the cDNA sequence confirms the neutrophil collagenase is a distinct gene product and a member of the family of matrix metalloproteinases.  相似文献   

15.
Evidence is presented that Achromobacter iophagus produces two distinct collagenases. Achromobacter collagenases A and B were separated by high-performance liquid chromatography from partially purified enzyme. The main collagenase, A (EC 3.4.24.8), which has been already described, was eluted in the region of molecular mass 110-90 kDa. A minor collagenase B eluted in the region of 320 kDa, although in SDS-gel electrophoresis the apparent molecular masses of its main active forms were estimated as 55 and 110 kDa. The specificities of collagenases A and B are different. Collagenase A splits in its synthetic substrate Pz-Pro-Leu-Gly-Pro-DArg the bond Leu-Gly, collagenase B does not split this substrate. Both collagenases split bonds Gln-Gly and Leu-Gly in synthetic peptides DNP-Pro-Gln-Gly-Ile-Ala-Gly-Gln-DArg-OH and DNP-Pro-Leu-Gly-Ile-Ala-Gly-DArg-NH2, respectively. Collagenase B is twice as active as A on the native collagen type I. Both enzymes are inhibited by EDTA. The antibodies raised against the human tooth collagenase specifically inhibited the collagenase B, but did not influence the activity of collagenase A. These results indicate, to our knowledge for the first time, an immunological relationship between a bacterial and a vertebrate collagenase.  相似文献   

16.
The gelatinolytic activity of rat uterus collagenase   总被引:6,自引:0,他引:6  
The collagenase produced by rat uterine cells in culture has been examined for its ability to degrade denatured collagen. Acting as a gelatinase, rat uterus collagenase was able to successfully degrade the denatured chains of collagen types I through V. In addition, the enzyme produced multiple cleavages in these chains and displayed values for Km of 4-5 microM, compared to values of 1-2 microM when native collagen was used as substrate. Furthermore, rat uterus collagenase degraded the alpha 2 chain of denatured type I collagen at a significantly faster rate than the alpha 1 chain, as previously observed for human skin fibroblast collagenase. In contrast to the action of human skin collagenase, however, the rat uterus enzyme was found to be a markedly better gelatinase than a collagenase, degrading the alpha chains of denatured type I guinea pig skin collagen at rates some 7-15-fold greater than native collagen. Human skin collagenase degrades the same denatured chains at rates ranging from 13-44% of its rate on native collagen. Rat uterus collagenase, then, is approximately 50 times better a gelatinase than is human skin collagenase. In addition to its ability to cleave denatured collagen chains at greater rates than native collagen, the rat uterus collagenase also attacked a wider spectrum of peptide bonds in gelatin than does human skin collagenase. In addition to cleaving the Gly-Leu and Gly-Ile bonds characteristic of its action on native collagen, rat uterus collagenase readily catalyzed the cleavage of Gly-Phe bonds in gelatin. The rat enzyme was also capable of cleaving Gly-Ala and Gly-Val bonds, although these bonds were somewhat less preferred by the enzyme. The cleavage of peptide bonds other than Gly-Leu and Gly-Ile appears to be a property of the collagenase itself and not a contaminating protease. Thus, it appears that the collagenase responsible for the degradation of collagen during the massive involution of the uterus might also act as a gelatinase to further degrade the initial products of collagenolysis to small peptides suitable for further metabolism.  相似文献   

17.
An assay for the quantification of collagen-like polymer (CLP) in Escherichia coli cells utilizing the specific reaction between collagenase and CLP is presented. It involves thermal treatment to precipitate non-CLP proteins, digestion of CLP by collagenase and detection of the absorbance of the liberated amino acids and peptides from CLP by a ninhydrin-based method. CLP concentration is determined from the absorbance measurement.  相似文献   

18.
The collagenase-producing bacterium tentatively called Empedobacter collagenolyticum was recently identified as Corynebacterium rathayii. Production of collagenase was studied in different media containing peptones or peptides of known sequences. A hexapeptide, Pro-Ala-Gly-Pro-Pro-Gly, is an inducer almost as good as collagen.  相似文献   

19.
Changes in interstitial collagenase activity in the rat uterine cervix during ripening were clarified in a time-dependent manner. Premature delivery was induced by an antiprogesterone agent, RU486, for rats in late pregnancy. The presence of interstitial collagenase in the extract from the rat cervical tissue was demonstrated, by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis using the natural and unaffected collagen as a substrate. The collagenase activity was determined as the release of digested peptides from the radio-labeled collagen. Our experiments with RU486 were performed in rats on the 18th day of pregnancy. A single administration of RU486 (15 mg/kg) resulted in the premature delivery of all treated rats within 30 h after the injection (average time was 23.9 h). The marked increase in cervical wet weight was observed up to the time to premature delivery along with a significant acceleration from 18 h after the administration of RU486. In this state, the cervical collagenase activity was enhanced, the highest levels being recorded at 21 h after the administration. The interstitial collagenase in the uterine cervix appears to play a significant role in the regulation mechanisms of cervical ripening in late pregnant rats.  相似文献   

20.
A fluorogenic substrate for vertebrate collagenase and gelatinase, Dnp-Pro-Leu-Gly-Leu-Trp-Ala-D-Arg-NH2, was designed using structure-activity data obtained from studies with synthetic inhibitors and other peptide substrates of collagenase. Tryptophan fluorescence was efficiently quenched by the NH2-terminal dinitrophenyl group, presumably through resonance energy transfer. Increased fluorescence accompanied hydrolysis of the peptide by collagenase or gelatinase purified from culture medium of porcine synovial membranes or alkali-treated rabbit corneas. Amino acid analysis of the two product peptides showed that collagenase and gelatinase cleaved at the Gly-Leu bond. The peptide was an efficient substrate for both enzymes, with kcat/Km values of 5.4 microM-1 h-1 and 440 microM-1 h-1 (37 degrees C, pH 7.7) for collagenase and gelatinase, respectively. Under the same conditions, collagenase gave kcat/Km of about 46 microM-1 h-1 for type I collagen from calf skin. Since both enzymes exhibited similar Km values for the synthetic substrate (3 and 7 microM, respectively), the higher catalytic efficiency of gelatinase reflects predominantly an increase in kcat. Both enzymes were inhibited by HSCH2(R,S)CH[CH2CH(CH3)2]CO-L-Phe-L-Ala-NH2 in this assay (50% inhibition at 20 nM and less than 1 nM for collagenase and gelatinase, respectively). Soluble type I collagen was a competitive inhibitor of peptide hydrolysis by collagenase (KI = 0.8 microM) and exhibited mixed inhibition of gelatinase (KI = 0.3 microM).  相似文献   

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