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

---

Query: EC:3.4.21.4 (trypsin)
42,187 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

At pH 5.5, sodium trifluoroacetate is a potent competitive inhibitor of porcine elastase (Ki = 2.6 mM) and human leukocyte elastase (Ki = 9.3 mM). For both enzymes the Ki increases strongly with pH. Sodium fluoride is inactive on pancreatic elastase and sodium acetate is a weak inhibitor of this enzyme. Trifluoroethanol inhibits both enzymes but is less active than trifluoroacetate in acidic pH conditions. Bovine trypsin and alpha-chymotrypsin are resistant to the action of sodium trifluoroacetate and trifluoroethanol. The interaction between sodium trifluoroacetate and pancreatic elastase is also demonstrated by 19F NMR spectroscopy. Trifluoroacetyltrialanine is able to displace trifluoroacetate from its complex with pancreatic elastase. In addition, a method using turkey ovomucoid for the active site titration of leukocyte and pancreatic elastase is described.
...
PMID:NMR and enzymatic investigation of the interaction between elastase and sodium trifluoroacetate. 2 76

Radioiodinated leukocyte elastase was found to bind rapidly and specifically to alveolar macrophages in vitro. In contrast to the binding of pancreatic and bacterial proteases, leukocyte elastase binding did not require the presence of alpha 2 macroglobulin. The binding was inhibited by an excess of unlabeled enzyme and was saturable by increasing elastase concentrations. Leukocyte elastase binding thus met criteria for receptor-mediated binding, with and estimated association constant of 4.97 x 10(5) M-1 and an estimated total of 640 x 10(6) binding sites/cell. It differed from the previously described binding of lysosomal glycosidases to macrophages in that it was insensitive to trypsin pretreatment, did not require calcium ions, and was not inhibited by yeast mannan. High-resolution autoradiography indicated that the cell-associated radiolabeled leukocyte elastase was rapidly incorporated into phagolysosomes. Macrophage binding may have a role in clearance of leukocyte elastase from tissue sites where alpha 2 macroglobulin is absent or present in low concentration. Thus, enzyme uptake by alveolar macrophages may be an important factor in the amelioration of lung tissue injury by extracellular leukocyte elastase.
...
PMID:Receptor-mediated binding and internalization of leukocyte elastase by alveolar macrophages in vitro. 8 20

The present work was undertaken to explore the effect of two purified neutral proteases derived from human peripheral blood polymorphonuclear leukocytes (PMN) on articular cartilage as a model of joint injury. Human leukocyte elastase and chymotrypsin-like enzyme, purified by affinity chromatography, released 32SO4 from labeled rabbit articular cartilage slices in vitro. Release of isotope was initially delayed, suggesting that either a lag in enzyme penetration occurs or that size of degradation fragments is a limiting factor in diffusion of label out of the tissue. The release of 35SO4 was inhibited by preincubation of elastase and chymotrypsin-like enzyme with human alpha 1-anti-trypsin, or with their specific chloromethyl ketone inactivators, and the action of elastase was also inhibited by a monospecific antiserum to PMN elastase, freed of major serum proteinase inhibitors. Immunohistochemical staining procedures revealed the presence of PMN elastase inside the matrix of cartilage slices after a 20-min exposure of tissue to either the pure enzyme or crude PMN granule extract. Serum alpha 1-antitrypsin failed to penetrate into the cartilage slices under identical in vitro conditions. In association with the results reported in the accompanying paper, these findings suggest a model of cartilage matrix degradation by PMN neutral proteases in which local protease-antiprotease imbalance, coupled with different rates of penetration of protease and antiprotease into target tissue, plays a key role in accounting for matrix damage.
...
PMID:Degradation of cartilage proteoglycan by human leukocyte granule neutral proteases--a model of joint injury. I. Penetration of enzyme into rabbit articular cartilage and release of 35SO4-labeled material from the tissue. 12 82

The synovial fluid (SF) of RA patients contains large amounts of PMN which are well equipped with neutral enzymes to degrade articular cartilage: elastase and cathepsin G, which both destroy proteoglycans and native collagen, as well as 2 types of collagenoases. Indirect evidence suggests that PMN might be important in the destruction of RA articular cartilage. In 19 SF of RA patients no free elastase or collagenase was found. Using immune histochemical methods, we observed that PMN and macrophages of SF contain both elastase and alpha 1-anti-trypsin and alpha 2-macroglobulin. Peripheral PMN - but not monocytes - contain elastase, however both types of cells lack alpha 1-antitrypsin and alpha 2-macroglobulin. Elastase is demonstratable in the superficial layer of pannus free RA articular cartilage. These findings suggest that neutral proteinases from PMN in RA SF are generally neutralized by physiologic inhibitors and removed by phagocytes. The enzyme-inhibitor interaction might be bypassed during "frustrated phagocytosis" so that enzymes like PMN elastase can damage RA articular cartilage.
...
PMID:[Chronic polyarthritis: role of polymorphonuclear leukocytes in the destruction of pannus-free articular cartilage]. 23 68

The interaction of human plasma alpha-1-antichymotrypsin with serine proteinases from different tissues has been investigated. The protein was found to form stable complexes with pancreatic chymotrypsin, leukocyte cathepsin G, and mast cell chymotrypsin. No inhibition of pancreatic trypsin or leukocyte elastase could be demonstrated. With mixtures containing both alpha-1-antichymotrypsin and alpha-1-proteinase inhibitor, it was found that the former preferentially inactivated leukocyte cathepsin G, while the latter showed a strong preference for pancreatic chymotrypsin. However, leukocyte elastase was specifically inactivated by alpha-1-proteinase inhibitor even in 1:1 mixtures with chymotrypsin. All of these results taken together suggest that one of the primary functions of alpha-1-antichymotrypsin is to inactivate leukocyte cathepsin G, while alpha-1-proteinase inhibitor controls the activity of other serine proteinases, particularly leukocyte elastase.
...
PMID:Human alpha-1-antichymotrypsin: interaction with chymotrypsin-like proteinases. 72 23

Serine proteinase inhibitory proteins (SPIs) were extracted from human disc tissues using 2 M GuHCl and subjected to CsCl density gradient ultracentrifugation. The SPIs recovered in the low buoyant density fractions (rho < or = 1.35 g/ml) were purified by a combination of gel-permeation, ion-exchange, trypsin affinity, and reverse-phase high performance chromatographies. Characterisation of the major disc SPI by polyacrylamide gel electrophoresis, isoelectric focussing, enzyme inhibition and pH stability studies indicated that this small molecular weight (12-14 kDa), highly basic (pI > 9.5), acid-stable but alkaline-labile protein possessed potent inhibitory activity against bovine pancreatic trypsin and chymotrypsin, and human leukocyte elastase and cathepsin G. Two-major and two-minor low molecular weight cationic SPI species were identified by reverse-phase HPLC. The predominant species was identical to a human articular cartilage SPI sharing amino terminal sequence homology with the mucus proteinase inhibitors (MPIs). It also cross-reacted with an antiserum to the MPIs and behaved identically to secretory leucocyte proteinase inhibitor (SLPI) when examined by reverse phase HPLC, and SDS PAGE. A higher molecular weight (54 kDa), anionic (pI approximately 4.6) SPI was also purified and identified as alpha 1-proteinase inhibitor (alpha 1-PI). Quantification of alpha 1-PI and the small molecular weight cationic disc inhibitors indicated that the latter were depleted in morphologically degenerate disc tissues while levels of alpha 1-PI were somewhat higher although a large proportion of the alpha 1-PI was inactive. A depletion of total SPI levels was evident overall in degenerate discs suggesting a functional role for these inhibitory proteins in the maintenance of IVD matrix homeostasis.
...
PMID:The serine proteinase inhibitory proteins of the human intervertebral disc: their isolation, characterization and variation with ageing and degeneration. 128 14

We investigated the effect of ulinastatin, a candidate anti-osteoarthritic drug, in comparison with indomethacin and triamcinolone, two well-known drugs for osteoarthritis, on IL-1 production by monocytes, proteoglycan synthesis by chondrocytes and superoxide generation by leukocytes. Ulinastatin, a glycoprotein purified from human urine, suppressed both the IL-1 production and the IL-1 induced reduction of proteoglycan synthesis. In addition, ulinastatin inhibited superoxide generation. These actions of ulinastatin seemed to be related to its inhibitory actions against serine proteases such as trypsin, alpha-chymotrypsin, plasmin, leukocyte elastase and leukocyte cathepsin G. Triamcinolone suppressed the IL-1 production more potently than ulinastatin and it also suppressed the IL-1 induced reduction of proteoglycan synthesis. Triamcinolone alone, however, reduced the proteoglycan synthesis, and it did not affect the superoxide generation. In contrast, indomethacin had no effect on proteoglycan synthesis and superoxide generation, although it accelerated the IL-1 production. These results indicate that these three drugs have different mechanisms of action on the factors involved in the pathogenesis of osteoarthritis. Since ulinastatin has broad actions, which are considered to be beneficial for preventing some process of osteoarthritic pathogenesis, ulinastatin is expected to be an useful drug for the treatment of osteoarthritis.
...
PMID:[Mechanism of the anti-osteoarthritic action of ulinastatin in comparison with those of indomethacin and triamcinolone]. 131 79

Matrix metalloproteinase 9 (MMP-9) has been purified as an inactive zymogen of M(r) 92,000 (proMMP-9) from the culture medium of HT 1080 human fibrosarcoma cells. The NH2-terminal sequence of proMMP-9 is Ala-Pro-Arg-Gln-Arg-Gln-Ser-Thr-Leu-Val-Leu-Phe-Pro, which is identical to that of the 92-kDa type IV collagenase/gelatinase. The zymogen can be activated by 4-aminophenylmercuric acetate, yielding an intermediate form of M(r) 83,000 and an active species of M(r) 67,000, the second of which has a new NH2 terminus of Met-Arg-Thr-Pro-Arg-(Cys)-Gly-Val-Pro-Asp-Leu-Gly-Arg-Phe-Gln-Thr- Phe-Glu. Immunoblot analyses demonstrate that this activation process is achieved by sequential processing of both NH2- and COOH-terminal peptides. TIMP-1 complexed with proMMP-9 inhibits the conversion of the intermediate form to the active species of M(r) 67,000. The proenzyme is fully activated by cathepsin G, trypsin, alpha-chymotrypsin, and MMP-3 (stromelysin 1) but not by plasmin, leukocyte elastase, plasma kallikrein, thrombin, or MMP-1 (tissue collagenase). During the activation by MMP-3, proMMP-9 is converted to an active species of M(r) 64,000 that lacks both NH2- and COOH-terminal peptides. In addition, HOCl partially activates the zymogen by reacting with an intermediate species of M(r) 83,000. The enzyme degrades type I gelatin rapidly and also cleaves native collagens including alpha 2 chain of type I collagen, collagen types III, IV, and V at undenaturing temperatures. These results indicate that MMP-9 has different activation mechanisms and substrate specificity from those of MMP-2 (72-kDa gelatinase/type IV collagenase).
...
PMID:Matrix metalloproteinase 9 (92-kDa gelatinase/type IV collagenase) from HT 1080 human fibrosarcoma cells. Purification and activation of the precursor and enzymic properties. 140 Apr 81

Procollagenase M(r) 85,000 (SDS-PAGE) was purified from buffy coat to homogeneity and represents a stable single polypeptide chain forming the entire proenzyme. The procollagenase can be activated by various proteinases, e.g. trypsin, chymotrypsin, cathepsin G, kallikrein and stromelysin and by different mercurial compounds. Proteolytic conversion of the latent enzyme to the active form by chymotrypsin is accompanied by a molecular weight reduction to an apparent M(r) 64,000. This active enzyme lacks the first 79 N-terminal residues. Activation by trypsin leads to a latent intermediate of apparent M(r) 70,000, lacking 48 N-terminal residues. The active enzyme is therefore generated upon prolonged incubation with trypsin by further cleavage of 22 N-terminal residues. Another latent intermediate form with apparent M(r) 69,000 is generated from the proenzyme upon incubation with leukocyte elastase by N-terminal cleavage of 53 or 64 residues, respectively. However, latent collagenase cannot be activated by plasmin. Activation by different mercurial compounds finally results in the formation of active collagenase with apparent M(r) 64,000. In contrast to the proenzyme, active collagenase can autolyse to give active M(r) 57,000 and 45,000 intermediates and two M(r) 28,000 fragments. Purification of latent leukocyte gelatinase yields three final products with apparent M(r) 98,000, 125,000 and 220,000 (SDS-PAGE; non reduced). Upon reduction, only the M(r) 98,000 form can be detected. The latent gelatinase can be activated in a similar manner as collagenase. Proteolytic activation by trypsin leads after N-terminal cleavage to an active gelatinase with sequence homology to leukocyte collagenase.
...
PMID:Latent collagenase and gelatinase from human neutrophils and their activation. 148 34

The role of the antiproteases alpha 1-proteinase inhibitor (alpha 1PI) and mucus proteinase inhibitor (MPI) in human lung emphysema was investigated by measuring their amount and functional activity against trypsin, leukocyte elastase, and pancreatic elastase in the bronchoalveolar lavage fluid (BALF). In addition, leukocyte elastase was quantified in the lavage samples by measuring the concentration of the elastase-alpha 1PI-complex. The study population consisted of 38 patients (5 nonsmokers, 8 former smokers, 25 smokers) with acquired emphysema (i.e., emphysema which is not caused by alpha 1PI deficiency), and 44 individuals (16 nonsmokers, 8 former smokers, 20 smokers) without emphysema. No differences were found between patients with and without emphysema in the activities of alpha 1PI and MPI, or in the concentration of alpha 1PI. The concentration of MPI was significantly higher in the BALF of patients with emphysema than in that of patients without emphysema (p = 0.025). A significantly higher concentration of elastase-alpha 1PI complex was found in patients with emphysema than in those without emphysema (p = 0.041). This finding could reflect the higher proteinase burden to which patients with emphysema are exposed. The increase of MPI in lavage fluid of patients with emphysema seems to be the result of increased production in emphysematous lungs. However, it remains unclear why patients develop emphysema while showing an increased content of MPI.
...
PMID:Alpha 1-proteinase inhibitor and mucus proteinase inhibitor in human lung emphysema. 152 Oct 41


1 2 3 4 5 6 7 8 9 10 Next >>

---