Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01189 (beta-endorphin)
 21,003 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Crude membranes (20,000 times g pellet) prepared from human, rat, and ovine adrenals bind 125-I-corticotropin-(1-24)-tetracosapeptide (125-I-ACTH-1-24) and degrade unbound hormone. The degradation is dependent on temperature and the concentration of membrane proteins. The degradation of 125-I-[9-tryptophan(o-nitrophenylsulfenyl)]-corticotropin-(1-24)-tetracosapeptide (125-I-NPS-ACTH-1-24) is similar to 125-I-ACTH-1-24, but that of 125-I-corticotropin-(11-24)-tetradecapeptide (125-I-ACTH-1-24 is inhibited by ACTH-1-24 and corticotropin-(1-10)-decapeptide (ACTH-1-10), but ACTH-11-24 at the same molar concentration has no effect. On the other hand, the degradation of 125-I-ACTH-11-24 is protected by ACTH-11-24 and ACTH-1-24, but not by ACTH-1-10. This suggests two systems of degradation, one will have the NH-2-terminal sequence of ACTH-1-24 as substrate, and the other the 11-24 COOH-terminal sequence. The main label product from the degradation of the 125-I-ACTH-1-24 and 125-I-ACTH-11-24 behaves as [125-I]monoiodotyrosine on Sephadex G-50 and paper chromatography. The independence of ACTH binding to its receptor and degradation is demonstrated by the following facts. (a) Calcium and pancreatic trypsin inhibitor completely inhibit the binding at concentrations when the degradation is not altered; (b) the sequences of peptides of ACTH which inhibit the binding and degradation of 125-I-ACTH-1-24 are different.
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PMID:Interactions of adrenocorticotropic hormone with its adrenal receptors. Degradation of ACTH-1-24 and ACTH-11-24. 16 55

When digestive enzymes are released into the blood, they may be completely inactivated by a variety of inhibitor present (alpha-1-protease inhibitor, antithrombin III, alpha 2-plasmin inhibitor, etc.) or only partially neutralized by alpha 2-macroglobulin. In this study, polarization fluorescence is used to demonstrate that complexes of alpha 2-macroglobulin with trypsin fluorescence is used to demonstrate that complexes of alpha 2-macroglobulin with trypsin can digest beta-endorphin, adrenocorticotropin, and beta-lipotropin. Furthermore, it has been shown that a small trypsin inhibitor (trasylol, mol. wt. 6500) can prevent this digestion, but that larger inhibitory proteins (i.e. soybean trypsin inhibitor, mol. wt. 21 500; alpha 1-protease inhibitor, mol. wt. 50 000) cannot.
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PMID:Polarization fluorescence studies on proteolytic activity of alpha 2-macroglobulin-trypsin complexes. 617 38

A chymostatin-sensitive angiotensin II-generating enzyme was found in human gastroepiploic arteries. The enzyme was purified using heparin affinity and gel filtration columns. The molecular mass of the purified enzyme was 30 kDa, and the optimum pH was between 7.5 and 9.0. Enzyme activity was inhibited by soybean trypsin inhibitor, phenylmethylsulfonyl fluoride and chymostatin, but not by ethylenediaminetetraacetic acid, pepstatin and aprotinin. The enzyme rapidly converted angiotensin I to angiotensin II (K(m), 67 mumol/l; Vmax, 43 pmol/s, kcat, 65/s), but did not hydrolyse angiotensin II, substance P, bradykinin, vasoactive intestinal peptide, luteinizing hormone-releasing hormone, somatostatin and alpha-melanocyte-stimulating hormone. The N-terminal sequence was identical to the sequence for human skin/heart chymase. Thus, the chymostatin-sensitive angiotensin II-generating enzyme in human vascular tissues is identified as chymase.
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PMID:Characterization of chymase from human vascular tissues. 935 25

A simple potentiometric procedure based on the determination of the primary amino groups in macromolecular polypeptides is presented. The method was found suitable for the detection of decomposition processes involving splitting of the peptide chain (liberation of primary amino groups) and deamination. The method has been applied to analysis of corticotropin fragments (ACTH(1-28) and ACTH(1-32)), Angiotensin II, and the basic trypsin inhibitor Kunitz base (Trasylol).
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PMID:Simple titrimetric method for the analytical control of macromolecular polypeptides. 1896 69