Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.21.4 (trypsin)
 42,187 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The composition of extracellular proteinases from Actinomyces fradiae 0072 and their effect on proteins and synthetic substrates were studied. The enzyme preparation was found to have keratinolytic, caseinolytic, collagenolytic, collagenase, trypsin-like, carboxy- and aminopeptidase activities. Five low molecular weight proteinases capable to hydrolyse keratin, casein, azocollagen were obtained via fractionation of the enzyme preparation on DEAE-cellulose and Sephadex columns. Proteinases from Act. fradiae and aminopeptidase with a molecular weight of 31,000 were shown to be different enzymes. In hydrolysis of L-leucyl-2-naphthylamide the Michaelis constant and Vmax of the enzyme were found to be 3.02 X 10(-3) M and 0.35 X 10(2) micronM/ml-min, respectively.
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PMID:[Characteristics of extracellular proteolytic enzymes of Actinomyces fradiae 0072]. 19 35

Elastolytic enzyme was purified and crystallized from culture fluid of Flavobacterium immotum No. 9-35. The purified enzyme was homogeneous on polyacrylamide gel electrophoresis. The molecular weight was determined by Sephadex G-100 gel filtration to be 13,000. The isoelectric point was between pH 8.3 and 8.9. The optimum pH of the enzyme was 7.2 for elastolytic activity. The purified enzyme showed not only elastolytic activity, but also non-specific proteolytic activity against various other proteins. Milk-clotting activity was also observed. The enzyme did not act on keratin, collagen, or fourteen amino acid esters, including N-benzoyl-L-alanine methyl ester, N-benzoyl-L-arginine ethyl ester, and N-acetyl-L-tyrosine ethyl ester, which were typical substrates of pancreatic elastase [EC 3.4.21.11], trypsin [EC 3.4.21.4], and chymotrypsin [EC 3.4.21.1], respectively. However, the enzyme selectively hydrolyzed elastin when both elastin and albumin were present in the reaction mixture. The enzyme was inhibited by o-phenanthroline and various heavy metals such as cadmium, lead, zinc, and mercury. Various inhibitors, such as diisopropyl phosphofluoridate, tosyl-L-lysine chloromethyl ketone, tosyl-L-phenylalanine chloromethyl ketone, trypsin inhibitor, iodoacetamide, etc., had no effect on the elastolytic activity.
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PMID:Purification and properties of elastolytic enzyme from Flavobacterium immotum. 23 95

The proteases of the larvae of the webbing clothes moth, Tineola bisselliella, were investigated because of this organism's phylogenetic rank as a member of the lower invertebrates, its unique position as one of the relatively few organisms that can digest keratin and its importance as a serious fabric pest. Both the number and nature of different proteolytic enzymes present were investigated and the various activities partially fractionated by ammonium sulphate precipitation and chromatography on DEAE-cellulose and Sephadex G200 columns. A complex mixture of peptidases and proteinases has been found in extracts of whole larvae and has been shown to be associated with the larval digestive tract. The proteinases include metal-chelator-sensitive proteinases (metalloproteinases) and serine proteinases but no SH-proteinases or acid proteinases. The serine proteinases include both trypsin-like and chymotrypsin-like activities. Four major and three minor anionic trypsin-like enzymes and a single major cationic trypsin-like enzyme have been detected. Only a single anionic chymotrypsin-like enzyme appears to be present. The trypsin-like enzymes are unaffected by the naturally occurring proteinase inhibitors, chicken ovomucoid, soybean trypsin inhibitor and lima bean trypsin inhibitor, while the chymotrypsin-like enzyme is inhibited by soybean trypsin inhibitor only. The enzymes resemble the serine proteinases from microorganisms in their pH stability. The peptidases include both aminopeptidase and carboxypeptidase activities and both are present in multiple forms. Sixteen aminopeptidase bands have been detected and all are present in individual larvae. They are not inhibited completely by reagents specific for any of the common active sites, and have different specificity requirements. Two carboxypeptidases have been detected on acrylamide gels and have been completely separated on DEAE-cellulose. No evidence could be found for the existence of any of these proteases as inactive precursors.
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PMID:Resolution of proteases in the keratinolytic larvae of the webbing clothes moth. 24 Mar 46

The fine structural morphology of the filiform papillae of the human tongue is investigated by transmission and scanning electron microscopy. Separation of the epithelium from the connective tissue by treatment with trypsin allows the demonstration of the three-dimensional structure of the primary and secondary connective tissue papillae and of the papillary epithelium. The distal surface of each primary connective tissue papilla is studded with secondary connective tissue papillae. Their lamellated surface structure corresponds with a complex system of cytoplasmic processes of the basal epithelial cells. The complicated surface architecture of the epithelial-connective tissue junction may suggest a close structural and functional relationship between the two types of tissues. There are two distinct cell populations forming the epithelial papilla, which differ in ultrastructural morphology from the basal cell layer to the surface of the epithelium. A dual pattern of keratinization, phylogenetically analogous to the hard and soft keratinization in rodent tongues, is found also in filiform papillai of the human tongue. The final product of epithelial differentiation is a type of keratin different from that in epidermal keratinocytes and in other regions of the oral cavity. The variability in size, shape and association with other organelles suggests the heterogenous nature of lingual keratohyaline granules. The predominance of Odland bodies of lamellated or of spoke type varies with the degree of keratinization of different regions of the papillary epithelium.
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PMID:[The ultrastructure of papillae filiformes of human tongue (author's transl)]. 116 22

The effect of sodium sulphite, cysteine, glutathione, mercaptoethanol and dithioerythritol (0.1-10 mmol l-1) on the activity of proteases of Microsporum gypseum was studied using azocasein, cross-linked bovine serum albumin and keratin as substrates. With the substrate without disulphide bonds (casein) no stimulation was found, and reducing agents inhibited proteolysis in most cases. With the remaining two substrates, all substances enhanced the activity of proteases probably through the cleavage of the substrate disulphide bonds. Sulphite was more effective than the four used thiols and enhanced the activity against serum albumin up to 3.2 times and against keratin up to 2.9 times. Using sulphitolysed sheep wool, keratinolytic activity increased after sulphitolysis of more than 20% of disulphide bonds. With the fully sulphitolysed wool the activity increased 43 times. The obtained results support the author's hypothesis on keratin degradation by sulphite excretion prior to attack by fungal proteases. Stimulation of proteolysis and keratinolysis by cleavage of disulphide bonds is not specific for dermatophytic proteases because trypsin and pronase behaved similarly in the experiments.
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PMID:Effect of reducing agents on proteolytic and keratinolytic activity of enzymes of Microsporum gypseum. 128 10

In order to clarify the molecular mechanism of blister formation in oral mucosa in pemphigus vulgaris (PV) comparing with that in epidermis, we analyzed the effects of PV serum on the distribution of keratin intermediate filaments (KIFs) and desmoplakins in oral as well as epidermal cultured keratinocytes by immunofluorescence microscopy using anti-keratin and anti-desmoplakin I/II monoclonal antibodies. After incubation with PV serum for 96 h at 37 degrees C, clusters of anti-keratin positive dots were formed around the nucleus in some of the keratinocytes from normal gingiva and soft palate but not in keratinocytes from tongue and skin, and desmoplakins also changed their distribution from linear arrangement at cell-cell contacts to clusters of dots around the nucleus in gingiva but not in epidermal keratinocytes. The dotted structures similar to those induced by pemphigus serum were formed also by incubation with human plasmin in gingival keratinocytes. However, no dot-formation of keratins was induced in these cells after incubation with trypsin. Furthermore, in epidermal keratinocytes, no keratin-dot formation was observed even after incubation with plasmin or trypsin. These results suggest that the dotted structures of KIFs caused by PV serum and plasmin might be a feature characteristic for the response of oral keratinocytes to PV serum and that there are some distinct differences in susceptibility to, and mode of, bulla formation between oral epithelium and epidermis.
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PMID:Different effects of pemphigus antibody and plasmin on the distribution of keratin intermediate filaments and desmoplakins between cultured oral and epidermal keratinocytes. 137 6

Autoantibodies to stratum corneum (SC) occur in virtually all normal adult human sera. These antibodies may be directed against various antigens of the SC. They have been detected by indirect immunofluorescence, passive hemagglutination (HA), immune adherence, and most recently by enzyme immunoassay and immunoblot methods. The purpose of our study was to examine whether antibodies to SC antigens as detected by passive HA are similar to the keratin intermediate filament (KIF) reactive antibodies. SC antigen preparation was prepared from psoriatic scales by the trypsin-phenol-water (TPW) extraction method. KIFs were prepared by 8 M urea extraction of normal callus or psoriatic scales. The anti-SC antibody titers of normal human sera were determined by passive HA before and after absorption with TPW-SC antigen preparation and upon absorption with KIFs. Similarly, titers of anti-KIF antibodies were determined on absorbed and unabsorbed sera by immunoblot assay. The results of this study indicate that the absorption of the sera with KIFs did not affect the titer of antibodies to TPW-extractable SC antigens whereas the titer of KIF antibodies dropped. KIF-reactive antibodies, on the other hand, were not affected by absorption with TPW-SC antigen, whereas the latter absorbed out the corresponding reactive antibodies. These results indicate that antibodies directed against SC antigen are different from the KIF-reactive antibodies.
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PMID:Stratum corneum antibodies detected by hemagglutination are not directed against keratin intermediate filaments. 169 42

A 47-year-old female was admitted for a right hypochondrial pain and was diagnosed as having a hepatic tumor with a cystic lesion. After a right and a caudal lobectomy, she died of hepatic failure due to a tumoral recurrence. At autopsy, a cystic tumoral nodule, 15 x 7 cm in size, and numerous other nodules were revealed in the liver. Metastases were seen in both lungs, the left kidney, the colon, the mesenterium, the peritoneum, the diaphragm, and the para-pancreatic lymph nodes. The hepatic tumors consisted of four types of tumor cells: spindle, round, mixed (spindle and round cells), and cells with pseudoalveolar features. All tumor cells showed a positive immunohistochemical reaction to polyclonal keratin, low molecular monoclonal keratin, alpha 1 anti-trypsin, vimentin and to actin in their cytoplasms. This is considered a very rare case.
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PMID:[A hepatocellular carcinoma showing sarcomatous features and an extensive metastasis]. 170 77

The antibodies of keratin and vimentin were used as the histochemical probes determined by the immuno-fluorescent technique to recognize the rat epididymal epithelial cells in the different ages from the connective tissue both in intact epididymides and in isolated cultured cells. It also showed that an enriched suspension of epididymal epithelial cells could be obtained by sequential digestion with 0.05% trypsin and 0.1% collagenase. The morphological characteristics were appeared during the cells in culture. Therefore the epididymal epithelial cells isolated and cultured by present methods could be used as a research model to study their functions.
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PMID:[The recognition of rat epididymal epithelial cells]. 170 22

We developed immunohistochemical and image analytical techniques to localize and quantify keratins and desmoplakins in sections of plastic-embedded human gingiva. Acetone fixation followed by plastic embedding of gingiva provided excellent morphology and permitted immunohistochemical detection of keratins 1 and 19 and desmoplakins I & II after 2.5-min trypsin digestion. Quantitative image analysis demonstrated that different volume densities of staining of each marker were associated with specific epithelial strata. Keratin 1 stained most heavily in granular strata, followed by corneal and spinous strata; keratin 19 stained most strongly in the basal layer; desmoplakins I & II stained most strongly in the granular and corneal strata. These findings confirm that variations of keratin and desmoplakin expression in these epithelial are associated with regional patterns of epithelial differentiation.
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PMID:Immunohistochemical localization and quantification of desmoplakins I & II and keratins 1 and 19 in plastic-embedded sections of human gingiva. 170 76


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