Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P15088 (mast cell)
 14,925 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We investigated the clotting associated with delayed hypersensitivity (DH) responses in the mouse by sensitizing the animals to the contactant oxazolone (Ox), and then administering 125I-guinea pig fibrinogen i.v. 10 to 30 min before antigen challenge 5 days later. Early (4 to 8 hr) contact sensitivity (CS) responses in immunized mice were barely detectable by three conventional measures of CS, but the total 125I-cpm in ears challenged with hapten was 3.6 to 4.5 X that in control ears challenged with vehicle alone; moreover, the amount of urea-insoluble cpm (cross-linked 125I-fibrin-associated cpm) in the reactions to Ox was 6.5-fold to 8.2-fold that present in the control reactions. In 24 hr reactions that were near peak intensity by measurements of ear swelling, ear weight ratios, and ratios of 125I-5-iodo-2-deoxyuridine-labeled leukocyte infiltration, the cpm in antigen-challenged ears exceeded that in control ears by 13-fold to 53-fold. In addition, antigen-challenged ears contained 27 to 300 X the urea-insoluble cpm present in control ears. 125I-Fibrin deposition was not a specific characteristic of CS reactions, because a small amount of urea-insoluble reactivity was also detected in some reactions to Ox in native mice. Nevertheless, the assay was exquisitely sensitive and readily detected quantitative differences between the immunologically specific and nonspecific reactions at very early intervals after challenge or with suboptimal doses of antigen. Furthermore, it was more sensitive than conventional tests of CS in detecting the reactions elicited in mice that had been passively sensitized to Ox by adoptive transfer of immune lymph node cells. Finally, we showed that the assay gave similar results when we tested CS reactions elicited in mast cell deficient WBB6F1-W/Wv and littermate normal (+/+) mice, demonstrating yet another similarity in the phenotype of DH reactions elicited in the presence or absence of mast cells.
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PMID:125I-fibrin deposition in contact sensitivity reactions in the mouse. Sensitivity of the assay for quantitating reactions after active or passive sensitization. 348 38

Unlike the pancreatic endopeptidase zymogens, procarboxypeptidase A is activated very slowly in vitro. The activation proceeds through the removal of about 100 amino acids away from the N-terminus of the chain. The cleavage of the susceptible bond(s) in monomeric and aggregated forms of bovine procarboxypeptidase A by catalytic amounts of trypsin was found to be very fast. However, as in the case of the porcine zymogen, the expression of the carboxypeptidase activity was considerably delayed by the inhibitory effect of the activation peptide which remains bound to the enzyme molecule after the trypsin treatment of the zymogen. alpha-Carboxypeptidase A was mainly formed under the relatively mild conditions used, indicating that the Arg-1-Ala+1 bond is probably the first to be cleaved during in vitro activation. The bovine carboxypeptidase activity was immediately and reversibly expressed upon dimethylmaleylation of the activation mixtures. This expression does not require full dissociation of the enzyme-peptide complex but merely a suitable change in its quaternary structure resulting from a modification of some electrostatic interactions upon dimethylmaleylation. Separation of bovine carboxypeptidase A from its activation peptide was only achieved upon filtration of the dimethylmaleylated mixtures in the presence of 6 M urea. The bovine activation peptide contains at least 93 amino acids compared to the 94 amino acids found by other authors for the rat and porcine peptides and sequencing of the first 53 amino acids showed a 75-85% homology with the latter two peptides.
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PMID:Further studies on the activation of bovine pancreatic procarboxypeptidase A by trypsin. 360 14

Gap junctions (GJ) isolated from rat hearts in presence of the protease inhibitor phenylmethylsulfonylfluoride (PMSF) contain a Mr 44,000 to 47,000 major polypeptide and have a urea-resistant layer of fuzz on their cytoplasmic surfaces, whereas junctions isolated without PMSF are proteolyzed to a Mr 29,500 polypeptide by a serine protease and have smooth cytoplasmic surfaces (C.K. Manjunath, G.E. Goings & E. Page Am. J. Physiol. 246:H865-H875, 1984). Rat liver GJ isolated with or without PMSF contain a Mr 28,000 polypeptide and have smooth cytoplasmic surfaces. Here we examine the origin, type and inhibitor sensitivity of the heart protease; why similar proteolysis is absent during isolation of rat liver gap junctions; and whether the Mr 44,000 to 47,000 cardiac GJ polypeptide is the precursor of the Mr 29,500 subunit. We show that the Mr 44,000 to 47,000 polypeptide corresponds to the unproteolyzed connexon subunit; that proteolysis of this polypeptide occurs predominantly during exposure to high ionic strength solution (0.6 M KI) which releases serine protease from mast cell granules; that this protease is inhibitable with PMSF and (less completely) soybean trypsin inhibitor and chymostatin; and that in vivo degranulation of mast cells by injecting rats with compound 48/80 fails to prevent breakdown of cardiac GJ during isolation. The results support the concept that GJ from rat heart and liver differ in protein composition.
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PMID:Proteolysis of cardiac gap junctions during their isolation from rat hearts. 400 96

A method is reported for the preparative isolation of the two forms of pro-(carboxypeptidase A) from pig pancreas: the monomer and the binary complex with pro-(proteinase E). This method, which is mainly based on chromatography on DEAE-Sepharose at pH 5.7, allows these proenzymes to be prepared more quickly and in safer conditions than with other reported methods. Undegraded and homogeneous carboxypeptidase A1 and A2 species (peptidyl-L-amino acid hydrolase, EC 3.4.17.1), in monomeric forms with high specific activity, are also obtained in high yield by controlled trypsin activation of either of the pro-(carboxypeptidases A) followed by chromatography on DEAE-Sepharose at pH 5.8 under dissociating conditions (7 M-urea).
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PMID:Preparative isolation of the two forms of pig pancreatic pro-(carboxypeptidase A) and their monomeric carboxypeptidases A. 405 13

1. The subunit structure of rabbit subcomponent C1q was examined in a previous publication (Reid et al., 1972). The present paper describes some aspects of the structure of the polypeptide chains derived from the molecule. 2. The three polypeptide chains, produced by performic oxidation, of rabbit subcomponent C1q were isolated by ion-exchange chromatography in 8m-urea on DEAE-cellulose. 3. Each chain was found to contain 15-18% glycine and significant amounts of the amino acids hydroxyproline and hydroxylysine. 4. By means of collagenase digestion it was shown that all three chains of rabbit subcomponent C1q contain collagen-like sequences of amino acids which constitute about 40% of each chain. 5. By use of carboxypeptidase A it was established, indirectly, that the collagen-like sequences, in one of the chains, are probably located near, or at, the N-terminal end of the chain. 6. Collagenase digestion and heating at 52 degrees C (but not at 49 degrees C) caused rapid loss of native rabbit subcomponent C1q haemolytic activity.
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PMID:Studies on the structure and activity of rabbit Clq (a subcomponent of the first component of complement). 437 40

1. On exhaustive digestion of carboxymethylated actin in 6m-urea solutions with carboxypeptidase A, 1 mole of phenylalanine was liberated/43000g. of protein. At a lower urea concentration and in the absence of urea, carboxymethyl-cysteine (CMCys) was also liberated. 2. Three cysteine-containing peptides were identified by the study of peptide ;maps' of tryptic digests of actin treated with thiol reagents. 3. The three peptides, each containing one residue of CMCys, were isolated from tryptic digests of carboxymethylated actin by ion-exchange chromatography. 4. One of these peptides was possibly the N-terminal peptide and contained about 17-18 residues; another was CMCys-Asp-Ile-Asp-Ile-Arg; the other, CMCys-Phe, was the C-terminal tryptic peptide. 5. The chemical evidence suggests that the actin molecule consists of a single polypeptide chain of molecular weight about 44000.
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PMID:Chemical studies on the cysteine and terminal peptides in tryptic digests of actin. 572 98

Two different isoenzymes of fructose-P2 aldolase can be resolved by chromatography of crude spinach leaf extracts on DEAE-cellulose columns. The acidic isoenzyme comprises about 85% of the total leaf aldolase activity. The two forms differ in primary structure as judged by their distinctive amino acid compositions, tryptic peptide patterns, and immunological properties. Only the acidic isoenzyme was detected in extracts of isolated chloroplasts, suggesting that this molecule represents the chloroplast form of spinach leaf aldolase while the basic isoenzyme is of cytosolic origin. The cytosolic (basic) isoenzyme and chicken aldolase A4 are similar in the following respects. 1) They have similar specific catalytic activity (10-15 units/mg); 2) they are both highly sensitive to inactivation by very limited digestion with bovine pancreatic carboxypeptidase A; 3) they both have subunit molecular weights of 40,000; 4) they both have derivatized (blocked) NH2-terminal structures; 5) they are both resistant to thermal denaturation at 50 degrees C; and 6) they both regain catalytic activity following reversible denaturation at pH 2.3 or in 5.8 M urea. Also, the cytosolic aldolase cross-reacted immunologically with the single aldolases present in spinach seeds and in wheat germ. Further, this isoenzyme readily "hybridized" with chicken aldolase A4 in vitro. These observations demonstrate the close homology between the cytosolic aldolases derived from plant and animal origins. The chloroplast aldolase had a specific catalytic activity of about 8 units/mg and, like its cytosolic counterpart, was severely inactivated by limited digestion with carboxypeptidase A. However, this isoenzyme was distinct from the cytosolic aldolase in the following characteristics: 1) its "small" subunit size (Mr congruent to 38,000); 2) its underivatized NH2-terminal structure; 3) its high sensitivity to thermal denaturation at 50 degrees C; and 4) its inability to refold into an enzymatically active conformation following denaturation at pH 2.3 or in 5.8 M urea. The distinctive properties of the chloroplast aldolase may be expected for an enzyme which is synthesized as a higher molecular weight precursor on cytosolic polysomes and is then proteolytically processed to the "mature" form during its migration into the chloroplast organelle.
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PMID:Isolation and characterization of the cytosolic and chloroplast forms of spinach leaf fructose diphosphate aldolase. 642 Mar 97

The phosphate transport protein from beef heart mitochondria has been purified on a large scale by hydroxylapatite chromatography in the presence of sodium dodecyl sulfate and urea. As shown by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (silver stain), the pure phosphate transport protein preparation consists of two protein bands (alpha and beta, ratio 1:1) with similar mobilities (34 kDa) which display identical peptide maps if fragmented with either CNBr or HCl/dimethyl sulfoxide/HBr. The complete amino acid composition of phosphate transport protein is presented. Quantitative determination of N-terminal amino acids underlines the purity of the preparation and shows for alpha and beta the identical amino-terminals H2N-Ala-Val-Glu-Glu-Glx-Tyr-. Qualitative digestion shows that carboxypeptidase A is able to release at least three amino acids from the C termini of the alpha as well as the beta band of phosphate transport protein. The nature of these two protein bands is discussed. The sum of phosphate transport protein (alpha + beta) per total mitochondrial protein amounts to 2.3% or 1.4 nmol of phosphate transport protein (34 kDa) per nmol of cytochrome b.
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PMID:Mitochondrial phosphate transport. Large scale isolation and characterization of the phosphate transport protein from beef heart mitochondria. 674 42

Tryptase, the predominant neutral protease in human mast cell secretory granules, was purified to homogeneity from dissociated and concentrated pulmonary mast cells by sequential chromatography on Dowex 1-X2, DEAE-Sephadex, and heparin-agarose. Purified tryptase gave a single stained protein band on polyacrylamide gels after electrophoresis at pH 4.3 in the presence of 4 M urea. The enzyme has an apparent molecular weight of 120,000 to 140,000 by gel filtration chromatography. Electrophoresis of purified tryptase under denaturing conditions revealed subunits with molecular weights of 37,000 and 35,000 in a molar ratio of 1:1, consistent with a tetrameric subunit structure for the holoenzyme of Mr = 144,000. Both subunits bind [3H]diisopropyl fluorophosphate as assessed by the correspondence of radioactivity with the two stained protein bands in a polyacrylamide gel after electrophoresis of purified tryptase under denaturing conditions, indicating that all four subunits of the holoenzyme may have active site capacity. Purified tryptase has a specific activity for tosyl-L-arginine methyl ester of 97 units/mg (1 unit = 1 mumol of substrate cleaved/min at 22 degrees C). Human pulmonary mast cells contain tosyl-L-arginine methyl ester-esterase at levels more than 100-fold higher than those of human neutrophils, eosinophils, and monocytes. One million mast cells contain about 1.1 units, or 6 to 19 micrograms of tryptase, and have the capacity to contribute dominant levels of this enzyme at tissue sites of mast cell degranulation.
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PMID:Tryptase from human pulmonary mast cells. Purification and characterization. 702 44

The activation peptide of the monomeric procarboxypeptidase A from porcine pancreas was isolated by means of controlled trypsin digestion of the proenzyme followed by ion-exchange chromatography under dissociating conditions (7 M urea). The molecular weight of the isolated peptide was estimated to be around 11500-12000 (corresponding to approx. 100-103 residues) as judged by SDS electrophoresis and amino acid analysis, a figure that agrees with the differences between the corresponding values for procarboxypeptidase A and carboxypeptidase A (peptidyl-L-amino acid hydrolase, EC 3.4.17.1). The activation peptide has a high content of hydrophobic and acidic amino acids, and lacks cysteine. A remarkable feature is the strong competitive inhibitory action of the peptide on both porcine and bovine pancreatic carboxypeptidase A activity, with a Ki in the nanomolar range, and its null ability to inhibit porcine pancreatic carboxypeptidase B (EC 3.4.17.2). The above properties, and the fact that the peptide has the same N-terminal residue (lysine) as the parent procarboxypeptidase A, suggest that the isolated peptide contains most (if not all) of the activation segment of the proenzyme.
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PMID:The severed activation segment of porcine pancreatic procarboxypeptidase A is a powerful inhibitor of the active enzyme. Isolation and characterisation of the activation peptide. 713 80


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