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

1. Evidence is given for the presence of at least five pepsinogens in a crude extract of mixed chicken stomachs. One of these was purified and could be activated to yield a single pepsin. 2. The molecular weights of the pepsinogen and pepsin were 36000 and 34000 respectively. The pepsin associated at low pH values and low ionic strength. 3. The amino acid analyses of both proteins are given. The pepsin was devoid of phosphate but contained carbohydrate. 4. The N-terminal amino acids of pepsinogen and pepsin were serine and threonine respectively. Five amino acids were released by carboxypeptidase A and it was deduced that serine may be the C-terminal one. 5. Each protein contained one thiol group per molecule as determined by titration with p-chloromercuribenzoate. The rate of the reaction was very rapid with pepsin, but much slower with pepsinogen, although the same group appeared to react in both instances. The enzymic activity of pepsin was unaffected by the modification. 6. The isoionic point of the pepsin was close to pH4.0 and the enzyme was stable for long periods at pH values up to 7.0. 7. The enzyme hydrolysed bisphenyl sulphite almost as rapidly as did pig pepsin A.
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PMID:The purification and properties of a single chicken pepsinogen fraction and the pepsin derived from it. 457 60

Two peptides rich in hydrophobic amino acids have been isolated from venom sacs of the European hornet, Vespa crabro. One peptide (P-2) is structurally and functionally related to the tetradecapeptide mastoparan and has been named mastoparan C. Leu-Asn-Leu-Lys-Ala-Leu-Leu-Ala-Val-Ala-Lys-Lys-Ile-LeuNH2. The other (P-1) is a tridecapeptide with a new sequence: Phe-Leu-Pro-Leu-Ile-Leu-Arg-Lys-Ile-Val-Thr-Ala-LeuNH2 which we have named crabrolin. The peptide releases histamine from rat peritoneal mast cells with a threshold of approximately 2.5 micrograms/ml (congruent to 8 microM). Crabrolin also facilitates the action of purified phospholipase A2 from different sources, but it is not quite as active as mastoparan. It is clearly less active than mastoparan in lysing erythrocytes, and it does not release amylase from dispersed guinea pig pancreatic acini. Given its unique sequence, the principal effect of crabrolin may be neither mast cell degranulation nor phospholipase facilitation, but a yet undiscovered action.
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PMID:Isolation and characterization of two new peptides, mastoparan C and crabrolin, from the venom of the European hornet, Vespa crabro. 620 53

The carboxy-terminal amino acids of a number of poliovirus proteins were determined by carboxypeptidase A analysis. The nonstructural proteins P3-2, P3-4b and their precursor. P3-1b, were found to be coterminal with a sequence of -Ser-Phe-COOH. As these proteins are coded for at the extreme 3' end of the viral RNA, it is possible to establish the termination site of translation at nucleotide 7,361, 73 nucleotides before the start of the polyadenylic acid tract of the RNA. Two additional nonstructural proteins, P2-X and its precursor, P2-3b, were also found to be coterminal with a sequence of -Phe-Gln-COOH. This result confirms the existence of at least one Gln-Gly proteolytic cleavage site. These Gln-Gly cleavage sites are predicted from the nucleotide sequence to be ubiquitous throughout the poliovirus genome. The only exceptions are the cleavage sites at the carboxy termini of the structural protein VP4 and VP1. Carboxypeptidase A analysis of VP1 establishes a terminal sequence of -Thr-Tyr-COOH, and similar analysis of VP4 shows Asn to be the terminal amino acid residue, observations that prove the existence of the exceptional C-terminal amino acids. In none of the analyzed cases has C-terminal trimming after cleavage been observed.
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PMID:Carboxy-terminal analysis of poliovirus proteins: termination of poliovirus RNA translation and location of unique poliovirus polyprotein cleavage sites. 628 38

Penicillinase from Bacillus cereus 569/H was purified to homogeneity. Its active site was probed by use of an affinity label generated in situ by the diazotization of 6-aminopenicillanic acid, a catalytically poor substrate for this enzyme. The loss of activity arising during the inactivation is dependent upon pH and the penicillin:sodium nitrite ratio used. Optimal inactivation was obtained at pH 4.7 and reactivation could be prevented if subsequent purification and manipulations were performed at low pH. Inactivation by diazotized 6-aminopenicillanic acid was characterized further by tryptic and chymotryptic digestion of the inactivated enzyme and peptide mapping of the resulting digests. Amino acid analysis of the chymotryptic labeled peptide yielded a composition which corresponds to residues 41-46 (Ala-Phe-Ala-Ser-Thr-Tyr) in the published partial sequence of the enzyme (Thatcher, D. (1975) Biochem. J. 147, 313-326). Further digestion of this chymotryptic peptide with carboxypeptidase A reveals that serine-44 is modified in this affinity labeling procedure. Mass spectral analysis of the modified serine residue and alkali-released label, and comparison with spectra of model compounds indicates that the inactivation occurs with rearrangement of the beta-lactamthiazolidine structure to a dihydrothiazine.
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PMID:Bacillus cereus 569/H penicillinase serine-44 acylation by diazotized 6-aminopenicillanic acid. 630 23

The proteolipid of rabbit sarcoplasmic reticulum was isolated and characterized. Tyrosine was identified as the C-terminal amino acid by hydrazinolysis and carboxypeptidase A digestion. The N-terminal sequence of proteolipid is: Met-Glx-Arg-Ser-Thr-Arg-Glx-Leu-Cys-Leu-Asp-Phe. The hydrophilic character of the N-terminal portion suggests that it is exposed on the membrane surface.
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PMID:Purification and characterization of the proteolipid of rabbit sarcoplasmic reticulum. 645 Jun 18

Multiple forms of urotensin II (UII), one of the hormonal peptides of the caudal neurosecretory system of fishes, were purified from the urophyses of the carp, Cyprinus carpio. Three distinct peaks with UII activity (classified as UII-alpha, -beta and -gamma) were separated by reverse-phase high-pressure liquid chromatography (HPLC). Edman degradation as well as digestion with carboxypeptidase A revealed the primary structures of these peptides as UII-alpha: Gly-Gly-Gly-Ala-Asp-Cys-Phe-Trp-Lys-Tyr-Cys-Val UII-beta: Gly-Gly-Ser-Asn-Thr-Glu-Cys-Phe-Trp-Lys-Tyr-Cys-Val UII-gamma: Gly-Gly-Gly-Ala-Asp-Cys-Phe-Trp-Lys-Tyr-Cys-Ile The results of thin-layer chromatography, HPLC, amino acid analysis, and sequencing indicate that UII-alpha and -gamma are homogeneous. UII-beta appears, however, to be a mixture of two components, differing only at position 2. Thus, in the carp urophysis, four forms of UII appear to be present, although the separation of two components in UII-beta has not been obtained. Sequence of positions 6-11 is common to all forms of UII isolated from the carp, sucker (Catostomus commersoni) and goby (Gillichthys mirabilis).
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PMID:Primary structures of multiple forms of urotensin II in the urophysis of the carp, Cyprinus carpio. 674 27

The preparation of N alpha 1 N epsilon 29-bis-methylsulphonylethyloxycarbonyl-des-alanineB30-B-chain-disulphide-O gamma 13 O gamma 21-dimethyl ester is described. Starting with the di-S-sulphonate-B-chain it was prepared by i) removal of the C-terminal amino acid by digestion with carboxypeptidase A, ii) reduction and oxidation to form the cyclic disulphide, iii) esterification of the three carboxyl groups (alpha COOH = LysB29, gamma COOH - GluB13 and GluB21) followed by selective tryptic hydrolysis of the alpha-carboxyl ester, and iv) the protection of both amino groups (alpha NH2 = PheB1, epsilon NH2 = LysB29). This B-chain derivative was activated selectively at the C-terminal carboxyl group by formation of a mixed anhydride, and condensed with the dipeptide Thr-Arg. All protecting groups were removed by treatment with alkali. The human-B-chain C-terminal elongated with Arg was obtained in a yield of 30% based on the protected des-AlaB30-B-chain derivative.
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PMID:Preparation of partially protected des-alanineB30-insulin-B-chain-disulphide and its use in semisynthesis. 675 63

An unusual type of posttranslational modification has been observed in a rat brain in vitro system. It consists in leucine addition to a preformed protein in such a way that the added leucine is not located at either the NH2 or the COOH terminus of the acceptor protein. The incorporation reaction requires ATP, ATP-generating components and tRNA. It is inhibited by aurintricarboxylic acid but does not require the presence of ribosomes or GTP. The incorporated leucine has a free NH2 group, and it is not released by leucine aminopeptidase or carboxypeptidase A. It is linked to the acceptor protein through a bond that is too alkali labile and too hydroxylamine labile to be a peptide bond. The simplest interpretation of the results consists in proposing that an ester bond is formed between the leucine and the side chain of a serine, threonine, or tyrosine in the acceptor protein.
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PMID:Transfer ribonucleic acid dependent but ribosome-independent leucine incorporation into rat brain protein. 717 78

Carboxypeptidase A gamma from porcine pancreas was purified to homogeneity by ammonium sulfate fractionation, autolysis, batch absorption and elution from DEAF-Sephadex, and crystallization. The overall purification was about 32-fold with a yield of 31% and the specific activity of the purified protein was 108 units/mg protein. The apparent relative molecular mass determined by gel filtration on a Sephadex G-200 column was 38 900. The amino-terminal sequence of the porcine carboxypeptidase A gamma was Asn-Tyr-Ala-Thr-Tyr-His-Thr-Leu-Glu-Glu-Ile-Tyr-Asp-Phe-Met-Asp-Ile-Leu-Val-Ala -Glu-His-Pro-Gln-Leu- which was highly homologous to that of bovine carboxypeptidase A gamma. The purified enzyme was characterized with respect to isoelectric point (4.3). Km for N alpha-carbobenzoxyglycyl-L-phenylalanine (Cbz-Gly-LPhe) (20 mM), amino acid composition, pH optimum, pH stability, stability at different temperatures and effect of drying. The enzyme contained 1.01 mol zinc/mol and was inhibited by chelating agents such as EDTA and o-phenanthroline. Among substrates such as Cbz-Gly-LPhe, N alpha-benzoylglycyl-L-arginine, various kinds of amino acid esters, casein and elastin, porcine carboxypeptidase A gamma showed an enzymatic activity only towards Cbz-Gly-LPhe and casein. These data are in good agreement with the substrate specificity of bovine carboxypeptidase A.
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PMID:Crystallization and properties of carboxypeptidase A gamma from porcine pancreas. 727 15

The immunosuppressive drugs FK506 and rapamycin bind to a family of intracellular proteins termed FK506-binding proteins (FKBP). FK506 and rapamycin inhibit lymphocyte-activation pathways by forming complexes with an FKBP; subsequently, the drug/FKBP complexes interact with target molecules involved in signal transduction. A key target of FK506/FKBP12 complexes is calcineurin, a calcium- and calmodulin-dependent serine/threonine phosphatase. In mammalian cells, rapamycin treatment is associated with inhibition of the activity of several cellular serine/threonine kinases, including p70 S6 kinase. These kinases may function in signaling pathways involving TOR gene producs, which have been shown to interact with rapamycin/FKBP12 complexes in vitro. To determine if FKBP12 mediates the effects of both FK506 and rapamycin in mammalian cells, we overexpressed FKBP12 in a murine mast cell line. Increased expression of FKBP12 resulted in increased sensitivity to FK506 and rapamycin, as measured by inhibition of calcineurin activity and p70 S6 kinase activity, respectively. In contrast, overexpression of FKBP25 had no effect on sensitivity to either drug. Two distinct point mutations in FKBP12, one altering a hydrophobic residue within the drug-binding pocket and the other changing a charged surface residue of FKBP12, abrogated its ability to mediate sensitivity to FK506 and rapamycin. These results establish that FKBP12 can mediate sensitivity to both FK506 and rapamycin in mammalian cells.
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PMID:FK506 binding protein 12 mediates sensitivity to both FK506 and rapamycin in murine mast cells. 753 90


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