Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.4.24.3 (collagenase)
18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

During 5 days of culture, explants of normal rabbit synovium produced no active collagenase, negligible latent collagenase, but significant levels of free collagenase inhibitor. Synovium from joints exhibiting a proliferative arthritis produced greatly elevated levels of collagenase; the appearance of active enzyme in the medium during the second day of culture was associated with the disappearance of free inhibitor. Enzyme levels in the media correlated well with the arthritic status of joints, when explants were prepared up to 10 weeks after the induction of the model arthritis. Synovium from the contralateral joints of rabbits with unilaterally induced arthritis produced no active collagenase, but approximately one-third as much latent collagenase as found with arthritic joints. Enzymatic activities against gelatin and cartilage proteoglycan substrates were demonstrated in synovial culture media in addition to collagenolytic activity. Gel filtration showed that these activities were not due to a single enzyme, and further characterisation confirmed that the enzymes were metalloproteinases. The results are considered in the light of published data, and the involvement of metalloproteinases and their specific inhibitor in the development of arthritic lesions is discussed.
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PMID:The production in culture of metalloproteinases and an inhibitor by joint tissues from normal rabbits, and from rabbits with a model arthritis. I. Synovium. 628 57

Primary cultures of bovine articular chondrocytes release a latent metalloproteinase which is activated by incubation with organomercurials to degrade proteoglycans. All the enzyme present in the culture medium is latent and binds to columns of heparin-Sepharose. The yield of activity from the heparin-Sepharose columns (measured after organomercurial treatment) is approximately 300-1000% depending on the chondrocyte culture batch. Recombination of column fractions shows that the increase in activity is due to the separation of an inhibitor of the metalloproteinase by the chromatographic step. The metalloproteinase inhibitor has a molecular weight of approximately 35000 (determined by Bio-Gel P-60 chromatography) and binds reversibly to columns of concavalin A-Sepharose. It is relatively heat stable (30 min at 60 degrees C) and resistant to inactivation by trypsin (2 h, 37 degrees C, 10 microgram/ml trypsin). The inhibitor is active against rat uterine collagenase and gelatinase but does not affect bacterial metalloproteinases such as thermolysin and Clostridium histolyticum collagenase.
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PMID:Characterization of the metalloproteinase inhibitor produced by bovine articular chondrocyte cultures. 631 63

Human gingival fibroblast procollagenase has been purified to apparent homogeneity from serum-free and serum-supplemented fibroblast culture medium by a combination of ammonium sulfate precipitation, CM-cellulose chromatography, and gel-filtration on Bio-Gel P-150. Sodium dodecylsulfate polyacrylamide gel electrophoretic studies suggests that the purified fibroblast proenzyme is comprised of two closely related zymogens with the estimated Mr of 57,000 and 52,000. Upon densitometric scanning of the gels, the ratio of the two proenzyme forms was about 1 : 4 (57 : 52 kdal). Limited proteolysis of the fibroblast procollagenase with trypsin resulted in the conversion of both proenzyme forms into active enzyme forms of Mr 48,000 and 44,000, respectively. Amino acid analysis of the active enzymes and proenzyme forms revealed that the active enzymes contained fewer basic amino acids than do the proenzyme forms. The purified trypsin-activated fibroblast collagenase hydrolyzed type I collagen fibrils, cleaved tropocollagen in solution at 24 degrees C into TCA and TCB fragments, and cleaved the synthetic peptide substrate, DNP-peptide III, at the Gly-Ile bond. The gingival fibroblast collagenase exhibited a pH optimum of 7.5, was completely inhibited by EDTA or dithioerythritol but was not inhibited by N-ethylmaleimide or phenylmethylsulfonyl fluoride, and appeared to cleave human type III collagen approximately 10-fold faster than homologous type I collagen. In addition, comparison of the biochemical properties of the precursor and active forms of human gingival fibroblast collagenase with the precursor and active forms of human skin fibroblast collagenase, previously characterized by Stricklin and co-workers (Biochemistry 17: 2331-2337, 1978), revealed that they were similar in Mr, amino acid composition, and substrate specificity. Furthermore, the human gingival and skin fibroblast procollagenases were immunologically identical.
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PMID:Human gingival fibroblast collagenase: purification and properties of precursor and active forms. 632 84

We studied the effects of retinoids on islet cell-to-cell adhesiveness and glucose-induced insulin release from rat islets. For adhesion studies, islets were dispersed using low concentrations of trypsin. Thirteen cis-retinoic acid (13 cis-RA) was added to a suspension of 15 X 10(5) islet cells and adhesion of cells was quantitated using a hemocytometer. For functional studies, we measured biphasic insulin release from collagenase-isolated perifused islets, dispersed cells, and single large aggregates (clumps) of islet cells. Thirteen cis-RA (10(-4) M) stimulated insulin secretion at 9.7, 12.5, 16.7, and 27.7 mM glucose. Maximal effects of 13 cis-RA (174% of control) were evident during second phase release at 9.7 mM glucose. Thirteen cis-RA (10(-7) and 10(-6) M) caused cells to adhere to each other, and at higher concentrations, 13 cis-RA caused dispersed cells to reaggregate into a single clump. These retinoid-induced clumps were perifused in a Bio-Gel P-2 gel column. Secretion from the clump was twofold greater than from an equal number of perifused dispersed cells. Electron microscopic and freeze-fracture examination of the clump showed reaggregated cells to be intact and the presence of gap junctions between cells. In conclusion, 13 cis-RA has marked effects on islet cell-to-cell adhesiveness. Trypsin-dispersed cells reaggregated by 13 cis-RA have anatomical contacts and secrete more insulin as an aggregate than as dispersed cells. Thirteen cis-RA increases insulin release possibly by increasing adhesion or interactions between beta-cells.
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PMID:Cellular mechanisms of insulin release. Effects of retinoids on rat islet cell-to-cell adhesion, reaggregation, and insulin release. 635 84

Certain physical properties of two molecular forms of short-chain (SC) cartilage collagen [Schmid, T. M., & Linsenmayer, T. F. (1983) J. Biol. Chem. 258, 9504-9509] have been determined. The 59K form has both a collagenous and a noncollagenous domain, and the 45K form has only the collagenous one. By circular dichroic spectropolarimetry, both forms show the characteristic spectrum of a collagen triple helix with a maximum ellipticity at 222 nm and a minimum at 197 nm. The denaturation temperature (Tm) of the helical structure of both forms, as monitored at 222 nm, is approximately 47 degrees C. Thus, the presence of the nonhelical domain does not greatly affect this property. After thermal denaturation, however, the renaturation of the 59K form is much more rapid than that of the 45K form, regaining greater than 60% of its helical structure within 40 min. The 45K form regains at most 15%, even after 24 h. Gel filtration on Sephacryl S-500, run under nondenaturation conditions, showed that the molecules renatured from the 59K form had regained a structure indistinguishable from native ones, while the 45K had not. The noncollagenous domain of the 59K form could be obtained by digestion with bacterial collagenase. This domain, as previously reported, contains no disulfide bonds. But, it is very stable, requiring both detergent and heating to separate its component chains. We hypothesize that the chains within this domain are tightly held together by strong, noncovalent forces, such as hydrophobic bonds, which are refractory to thermal denaturation. These maintain the chains in proper registry, thus facilitating rapid renaturation of the helical domain.
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PMID:Denaturation-renaturation properties of two molecular forms of short-chain cartilage collagen. 670 82

Interactions between C1q and collagen are thought to be due to the similarity in the structure of collagen and part of C1q. In the present paper immunological and biochemical aspects of this similarity were explored. It was found that one of nine rabbit anticollagen sera studied showed a clearcut reactivity with C1q, while anticollagenantibody-positive sera and synovial fluids of patients with rheumatoid arthritis did not display any cross-reactivity with C1q. Eleven of twenty collagen-immunized guinea pigs, however, demonstrated cellular cross-reactivity with CLF, the collagen-like fragment of C1q. Gel filtration studies indicated the formation of complexes between CLF and collagen, simulating immunological inhibition of anti-C1q-antibody by collagen. Human RA synovial collagenase was found capable of splitting C1q at a position within its collagen-like fragment. The importance of the interactions between collagen and C1q for the pathological events characterizing RA is discussed.
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PMID:[Interactions between collagen and C1q: their significance for rheumatology]. 700 53

The collagenase domain of bovine glomerular basement membrane was isolated in soluble form after limited digestion with pepsin. Gel filtration chromatography of the domain under denaturing conditions revealed that most of the polypeptide constituents exhibit apparent molecular weights greater than the type I collagen beta-chain, while approximately 15% are similar in size to that of alpha-chain. Carboxymethyl cellulose chromatography of the alpha-size region revealed that 70% of the protein was polypeptide XIV, as previously designated (West, T. W., Fox, J. W., Jodlowski, M., Freytag, J. W., and Hudson, B. G. (1980) J. Biol. Chem. 255, 10451-10459). This polypeptide exhibits an apparent molecular weight of 102,000 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. An absolute molecular weight value of 86,000 was determined by sedimentation equilibrium ultracentrifugation in 6 M guanidine hydrochloride. About 15% of the mass is carbohydrate which exists in the form of glucosylgalactosylhydroxylysine. Thus, the polypeptide backbone has a molecular weight of 73,000, a value which is considerably smaller than the alpha-chains of classical collagen. The amino acid and carbohydrate composition and cyanogen bromide patterns indicate that polypeptide XIV has a structure similar to that of C-chain or alpha 1 (IV) collagen which has been identified in other tissues. In addition, the cyanogen bromide pattern of the entire collagenous domain is similar to that of polypeptide XIV, suggesting that the latter is a structural segment of many of the higher molecular weight components.
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PMID:Bovine glomerular basement membrane. Characterization of an alpha-size collagenous polypeptide. 725 9

Hepatocytes were isolated from catfish (lctalurus melas) by conventional collagenase digestion. Sensitivities of liver cells isolated from the same fish to the glycogenolytic action of epinephrine, mammalian glucagon, catfish glucagon, catfish glucagon-like peptide, synthetic fragment 19-29 of anglerfish glucagon I, fragment 19-29 of anglerfish glucagon II, and anglerfish glucagon II were compared in two different systems: perifusion in a Bio-Gel P4 column and flask incubation. Both experimental procedures were continued for a total of 100-120 min, while hormones were applied simultaneously to both preparations for 10 min. Effluent fractions from the columns and incubation media from the flasks were collected for glucose determination. The hormonal effects were clearly enhanced in perifused cells compared to those in cells incubated in flasks, the effect being especially evident at physiological concentrations of hormones. The hormonal effects in both systems were dose-dependent. Epinephrine and mammalian glucagon (10 nM), applied separately to the same column, produced two different peaks, glucagon causing more glucose production than epinephrine. In the presence of 0.4 mM glucose in the perifusion system, hormonal effects were diminished, implying that glucose accumulation during incubation of liver cells in flasks might affect hormonal effects. The results obtained in this study indicate that piscine hepatocytes suspended and perifused in a Bio-Gel column are more sensitive to physiological concentrations of glycogenolytic hormones and may represent a new tool for experimental studies of fish liver metabolism and its hormonal regulation.
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PMID:Hormone responsiveness of isolated catfish hepatocytes in perifusion system is higher than in flasks incubation. 792 55

Quantitative analysis of proteoglycans (PGs) revealed that the content of PG material from cryopreserved aorta, measured as uronate-positive material, was similar to that from fresh tissue (440 +/- 30 versus 430 +/- 7 micrograms/g wet tissue). Gel permeation column chromatography studies suggested that three PG fractions from cryopreserved tissue had molecular weights similar to PG fractions from fresh tissue; K(av) = 0.13, 0.47 (I), 0.20 (II), and 0.43 (III) from cryopreserved tissue and K(av) = 0.13, 0.50 (I), 0.23 (II), and 0.40 (III) from fresh tissue. Sequential extraction of tissue with guanidine-HCl (Gdn-HCl) followed by digestions with collagenase, elastase, and papain also demonstrated that there was no difference between fresh and cryopreserved tissues in the distribution of PGs in the extracts. Transmission electron microscopy analysis revealed less densely packed collagen fibers in cryopreserved tissues compared to fresh tissues. These studies indicate that there is no significant alteration in the content, molecular size, or distribution of PGs in properly cryopreserved tissue.
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PMID:Proteoglycan content in fresh and cryopreserved porcine aortic tissue. 800 93

Surfactant protein A (SP-A), with a reduced denatured molecular mass of 26-38 kDa, is characterized by a collagen-like sequence in the N-terminal half of the protein. This protein forms an oligomeric structure which is dependent upon this collagenous domain. SP-A has been demonstrated to function as an inhibitor of phospholipid secretion by primary cultures of alveolar type II cells via a cell surface receptor for the protein. However, the receptor-binding domain of SP-A has not been identified. The purpose of the present study was to investigate the role of the C-terminal domain of SP-A in binding to type II cells and regulation of phospholipid secretion. A monoclonal antibody to human SP-A, whose epitope was localized at the C-terminal domain of the protein, abolished the inhibitory activity of human SP-A on lipid secretion by type II cells, and attenuated the ability of human SP-A to compete with 125I-(rat SP-A) for receptor binding. SP-A was then digested with collagenase and the collagenase-resistant fragment (CRF), which is the C-terminal domain of SP-A (thus lacking the N-terminal domain), was isolated. Gel filtration chromatography revealed that CRF exists as a monomer in solution containing Ca2+. CRF had the ability to inhibit phospholipid secretion, although at a higher concentration than for SP-A, and was also able to compete with 125I-(rat SP-A) for binding to type II cells. A direct binding study showed that CRF bound to type II cells in a concentration-dependent manner. The present study demonstrates that the non-collagenous, C-terminal, domain of SP-A is responsible for the protein's inhibitory effect on lipid secretion and its binding to type II cells.
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PMID:Role of the C-terminal domain of pulmonary surfactant protein A in binding to alveolar type II cells and regulation of phospholipid secretion. 847 Oct 56


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