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)

The synthesis of the mast cell-degranulating peptide by liquid-phase fragment condensation is described. After the carboxyterminal of the peptide is condensated with polyethylene-glycol (Mr 10000) the following fragments are coupled stepwise on the polymer, a soluble carrier in dichloromethane by the dicyclohexylcarbodiimide/hydroxybenzotriazole-method. Pos. 17-21 Boc-Lys(Z)-Ile-Cys(SiPr)-Gly-Lys(Z) (I) Pos. 12-16 Boc-Pro-His(Trt)-Ile-Cys(Trt)-Arg(Tos) (II) Pos. 8-11 Boc-His(Trt)-Val-Ile-Lys(Z) (III) Pos. 5-7 Boc-Cys(SiPr)-Lys(Z)-Arg(Tos) (IV) Pos. 1-4 Boc-Ile-Lys(Z)-Cys(Trt)-Asn(Mbh) (V) It is practical to crystallize the polyethyleneglycol peptide-coupling products from ethanol after each step. Most of the protecting groups can be removed by treatment of the complete polyethylene-glycol-peptide in trifluoroacetic acid/HBr. In methanol, saturated with ammonia, the peptide is removed in the amid-form from the carrier. The guanidyl-blocking group disappears by solving the peptide in liquid HF. The crude peptide is converted into the tetra-S-sulfonate derivate by oxidative sulfitolysis and purified by ion-exchange and gel chromatography. After reduction by mercaptoethanol a cautious air-reoxidation of the SH- to the SS-peptide followed. Rechromatography on ion-exchange and dextran gels yields a peptide with good biological activity in rat cell histamin-liberation and inflammation inhibition compared with the natural recombinated product.
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PMID:[Basic peptides from bee venom, IV. Synthesis of the mast cell-degranulating peptide by liquid-phase fragment condensation (author's transl)]. 738 Mar 91

We investigated the degradation of angiotensin I (Ang I) by guinea pig aqueous humor at physiological pH (pH 7.4) and assessed the activity of responsible enzymes using various enzyme inhibitors. The aqueous humor was incubated with Ang I in the presence or absence of an enzyme inhibitor at 37 degrees C for the appropriate time period. The resulting peptides were analyzed by a Beckman HPLC system with a Waters microBondapak C18 analytical column using a 30-min increasing linear gradient of 10 to 40% acetonitrile containing 0.05% trifluoroacetic acid (TFA) and H2O containing 0.05% TFA at a flow rate of 1 mL/min. Detection was done by absorbance at 214 nm. Angiotensin II (Ang II) was a major product (39.3+/-4.10 nmol x h(-1) mL(-1), n = 5) of Ang I hydrolysis. Traces of angiotensin 1-9, angiotensin IV, and angiotensin 1-7 were also produced. Chymostatin (0.05 mmol/L), EDTA (1 mmol/L), enalaprilat (0.1 mmol/L), and ebelacton B (0.01 mmol/L) inhibited generation of Ang II from Ang I by guinea pig aqueous humor by 89+/-4.6, 56+/-7.6, 33+/-5.1, 20+/-6.5%, respectively. Our findings indicate that guinea pig aqueous humor contains several enzymes that can form Ang II. The chymostatin-sensitive type of enzyme was the most active one found in guinea pig aqueous humor. Angiotensin I converting enzyme, carboxypeptidase A, and deamidase may also contribute to angiotensin II formation in guinea pig ocular fluid.
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PMID:Metabolism of angiotensin I by guinea pig aqueous humor. 1147 97

An asymmetric total synthesis of the mast cell inhibitor (+)-monanchorin is reported in which a Sharpless AD on 11 and a cyclic sulfate ring opening with an azide feature as key steps. After further manipulation, a novel guanidine-controlled ester reduction provided the guanidine-hemiaminal 25 which underwent Wittig olefination to give 27. Hydrogenation and a second guanidine-controlled reduction of the ester in 28, to obtain aldehyde 29, then set up a trifluoroacetic acid mediated cyclization to give (+)-monanchorin TFA salt.
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PMID:A new stereocontrolled total synthesis of the mast cell inhibitory alkaloid, (+)-monanchorin, via the Wittig reaction of a stabilized ylide with a cyclic guanidine hemiaminal. 2470 42

The LC methods for related proteins prescribed in the European Pharmacopoeia monographs for insulins and insulin analogues are very similar and present some drawbacks including long run time and low resolution. LC to UHPLC-UV geometrical transfer was attempted to overcome such drawbacks. With the new UHPLC method, additional substances were separated in bovine and porcine insulins. A UHPLC MS-compatible method was developed using a mixed-mode C18 stationary phase with charged surface hybrid technology and a mobile phase containing a low concentration of trifluoroacetic acid and acetonitrile. An unknown peak was detected and identified as being B30-des-Alanine-insulin which was also confirmed by microTOF direct infusion and specific digestion with bovine carboxypeptidase A. Based on the results obtained during geometrical method transfer, a single UHPLC-UV method for human, bovine, porcine insulins and insulin lispro and aspart was developed and validated according to ICH Q2 guidelines. The new method is superior to the current European Pharmacopoeia LC methods with improved selectivity and shorter run time. The method is based on gradient elution and employs a commonly available stationary phase (conventional C18 column) which makes it an appropriate method for pharmacopoeial public quality standards. It may therefore represent a valid alternative to the LC methods currently described in the European Pharmacopoeia for insulins.
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PMID:Development and validation of a new UHPLC method for related proteins in insulin and insulin analogues as an alternative to the European Pharmacopoeia RP-HPLC method. 3061 63