Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P20366 (substance P)
 21,176 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Acid and neutral proteinases were isolated with the purpose of investigating their participation in the breakdown of hypothalamic peptides and proteins. The acid proteinase was purified about 1000-fold from hypothalamus by precipitation with acetone, chromatography on SP-Sephadex G-50, gel filtration through column of G-100 and chromatography on DEAE-Sephadex A-50. The molecular weight of the enzyme was approximately 50.000. Maximal activity against hemoglobin was obtained at pH 3,2--3,5: serum albumin was split much more slowly. Hypothalamus acid proteinase was partially inhibited by beta-phenyl pyruvate, benzothonium cloride, and was completely inhibited by low concentrations of pepstatin. This proteinase splits somatostatin, Substance P and some C-fragments of Substance P. The probable sites of enzyme action on these peptides were determined by the end group dansyl technique. Neutral proteinase was isolated from the supernatant fraction(100.000 g) of a 0,3 M sucrose homogenate of bovine hypothalamus by chromatography on DEAE Sephadex A-50, gel filtration through Sephadex G-100 and rechromatography on DEAE sephadex A-50 using luliberin as substrate. The rates of breakdown of luliberin and denaturated hemoglobin were measured by fluorometric estimation of acid-soluble peptides wieht o-phthaldialdehyde. The purifed enzyme preparations have a pH optimum of activity at 7--7,5. The enzymes molecular weight was approximatelyy 30--40.000. Enzyme activity was inhibited by L-1-tosylamide-2-phenylethylchloromethyl ketone, p-chloromercuribenzoate and divalent ions Co2+, Zn2+ and was significantly enhanced by dithiothreitol. The Km values for the reaction of hydrolysis of luliberin and hemoglobin were 1,33.10(-5) and 5,2.10(-5) M respectively. The neutral proteinase from the hypothalamus cleaves luliberin, somatostatin and Substance P. Sites of action of the enzyme upon those peptides were determined by means of the dansyl technique. The acid proteinase, most likely cathepsin D, and neutral proteinase from hypothalamus, may play an important role in the formation and breakdown of peptide hormones in the hypothalamus.
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PMID:[Breakdown of luliberin, somatostatin and substance P as an effect of hypothalamic endopeptidases]. 4 63

An enzyme which catalyzes the deamidation of thyroliberin (TRF; less than Glu-His-Pro-NH2) has been purified 110-fold from extracts of bovine anterior pituitary by ammonium sulfate fractionation, ion exchange chromatography on DEAE-cellulose, and gel filtration. This enzyme of 76,000 molecular weight (as estimated by gel filtration) exhibits maximal activity at neutral pH (optimum pH 7.4 to 7.6) in buffers of high ionic strength supplemented with thiol-protecting agents. As indicated by the strong inhibition of the enzymatic activity by N-ethylmaleimide and Hg2+, as well as by the extreme sensitivity toward diisopropyl fluorophosphate, -SH, and -OH residues apparently represent essential functional groups of the enzyme. The stereospecific deamidation of TRF (Km = 4.1 . 10(-4) M) is inhibited competitively by TRF analogues which contain proline or by the proline containing biologically active peptides luliberin (LH-RF), oxytocin, vasopressin, angiotensin II, and Substance P. TRF analogues without proline or peptide amides without proline are ineffective. This enzyme cleaves the appropriate Pro-X bonds in luliberin, angiotensin II, pyroGlu-His-Pro-Gly-NH2, and the collagenase substrate Z-Gly-Pro-Leu-Gly-Pro. Thus, it may be characterized as a post-proline-cleaving enzyme.
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PMID:Characterization of "thyroliberin-deamidating enzyme" as a post-proline-cleaving enzyme. Partial purification and enzyme-chemical analysis of the enzyme from anterior pituitary tissue. 11 64

Several N-carboxyalkyl peptides were synthesized and tested as inhibitors of pig synovial collagenase, 72-kDa gelatinase and stromelysin (matrix metalloproteinases MMP-1, MMP-2, and MMP-3). The most potent of the series, CH3CH2CH2(R,S)CH(COOH)-NH-Leu-Phe-Ala-NH2, competitively inhibited cleavage of dinitrophenyl-Pro-Leu-Gly-Leu-Trp-Ala-D-Arg-NH2 at the Gly-Leu bond by MMP-1 and MMP-2 (KI = 30 and 40 microM, respectively). A similar inhibitory potency was found for MMP-1 with soluble Type I collagen and MMP-3 with substance P as substrate. The inhibitor was coupled to EAH-Sepharose 4B through a C-terminal amide. In the presence of 2 M NaCl at pH 7.2, this matrix bound MMP-1, MMP-2, and MMP-3 from concentrated culture medium of pig synovial membranes. The enzymes coeluted at pH 4.1 and subsequently were resolved by chromatography on DEAE-Sephacel and heparin-Sepharose. Purified MMP-1 catalyzed the o-phenanthroline-sensitive cleavage of collagen into TCA and TCB fragments as well as slower hydrolysis of the alpha 2 chain. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of MMP-1 indicated a predominant polypeptide of approximately 44 kDa and minor species of approximately 24 and 21 kDa. The 44-kDa species and one of the smaller polypeptides reacted with an antiserum to residues 195-207 of human fibroblast MMP-1, indicating that porcine MMP-1 contains a similar sequence and that the smaller components were probably derived from MMP-1. Neither MMP-2 nor MMP-3 reacted with this antiserum. Purified porcine MMP-2 degraded gelatin but not collagen and exhibited an apparent Mr of approximately 71 kDa. Additional smaller polypeptides were present, one of which may correspond to tissue inhibitor of metalloproteinases. MMP-3 showed doublets of approximately 47/46 and 26/25 kDa and cleaved substance P at the Gly6-Phe7 bond. This procedure provides a rapid means of obtaining all three MMPs from one source in approximately 15% yield each.
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PMID:Application of N-carboxyalkyl peptides to the inhibition and affinity purification of the porcine matrix metalloproteinases collagenase, gelatinase, and stromelysin. 165 8

From rat brain, a membrane bound substance P-degrading endopeptidase (SPE) was purified 1580 fold to near homogeneity. After extraction with 10 mM CHAPS, the enzyme preparation was subjected to ion exchange chromatography on DEAE-cellulose, adsorption chromatography on hydroxyapatite, gelfiltration through Ultrogel AcA 44 and FPLC on Mono Q. This enzyme of 70,000 molecular weight is optimally active at pH 7.5. Metal chelators (EDTA and EGTA) and sulfhydryl modifying reagents (N-ethylmaleimide and p-chloromercuriphenylsulfonic acid) are strongly inhibitory while the serine-protease inhibitor diisopropyl-fluorophosphate does not effect the enzyme activity. The enzyme is strongly inhibited by bacitracin but not by phosphoramidon and captopril. Degradation of substance P is strongly inhibited by neurotensin, somatostatin, ACTH 1-39, and less effectively by LHRH but not by Leucine-enkephalin. Substance P is preferentially hydrolyzed at the Gln6-Phe7 peptide bond but fragmentation at the Pro4-Gln5, Gln5-Gln6,Phe7-Phe8 and Gly9-Leu10 bonds was also observed.
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PMID:A membrane bound substance P degrading endopeptidase from rat brain. 244 28

Ultraviolet irradiation of calmodulin in the presence of calcium results in either the intramolecular cross-linking of Tyr99 and Tyr138 [Malencik, D.A., & Anderson, S.R. (1986) Biochemistry 25, 709] or, when [Tyr8]substance P is bound, the generation of peptide-calmodulin adducts. The latter consist of two chromatographically distinct fractions, one of which was purified to homogeneity with phenylagarose, DEAE-Sepharose, and reverse-phase chromatography. Chemical characterization shows that the purified conjugate contains 1 mol/mol of peptide covalently attached to Tyr138 of calmodulin. The fluorescence intensity and anisotropy of the dityrosine moiety demonstrate that this novel derivative undergoes interactions with calcium, smooth muscle myosin light chain kinase, and phenylagarose which are similar to those of unmodified calmodulin.
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PMID:Peptide cross-linking to calmodulin: attachment of [Tyr8]substance P. 245 50

A novel substance P-degrading endopeptidase has been solubilized with Brij 35 from a membrane fraction of rat brain and purified by a procedure involving DEAE-cellulose chromatography, hydroxyapatite chromatography, Sephadex G-100 gel filtration, and Mono-Q HPLC. The activity of the degrading enzyme was monitored by measuring the disappearance of substance P by means of a bioassay and HPLC. SDS-polyacrylamide gel electrophoresis under reducing conditions of the enzyme gave a single band corresponding to a molecular weight of 58,000. The molecular weight of the enzyme was estimated to be 55,000 by gel filtration and the optimum pH for its activity was 7.5.. The purified enzyme cleaved substance P at three bonds, Pro4-Gln5, Gln5-Gln6, and Gln6-Phe7, in the ratio of 2:2:3. EDTA, o-phenanthroline, and p-chloromercuribenzenesulfonic acid strongly inhibited the enzyme, while diisopropyl fluorophosphate, E-64, Z-Gly-ProCH2Cl, phosphoramidon, and captopril had little or no inhibitory effect on it. The cleavage of substance P by the rat brain synaptic membrane was also analyzed under the conditions with or without these inhibitors. The inhibitor-susceptibility of the cleavage sites suggests that the present enzyme, together with endopeptidase-24.11, is involved in the degradation of substance P in the synaptic region.
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PMID:Purification and characterization of a substance P-degrading endopeptidase from rat brain. 246 57

A metastasis to the right liver lobe of an argyrophil/argentaffin midgut carcinoid tumour in a patient with the classical carcinoid syndrome was examined for the presence of tachykinins other than substance P, using a specific antiserum. The extract was initially purified using SepPak cartridges, and subsequently subjected to cation-exchange chromatography on SP Sephadex C-25 which separated the immunoreactive material into two main components (components I and II). Both were further purified by anion-exchange chromatography on DEAE-Sephadex A-25, and by reverse-phase fast protein liquid chromatography. Component II was identified as neurokinin A by its immunochemical and chromatographic properties and amino acid sequence analysis. Component I consisted of two molecular forms which were identified as neurokinin A(3-10) and neurokinin A(4-10) by amino acid sequence analysis. The tumour tissue contained only small amounts of the eledoisin-like peptide that has earlier been demonstrated in mammalian tissues. Although this component behaved like the nonmammalian peptide eledoisin on reverse-phase HPLC and on reverse-phase ion-pair chromatography, eledoisin-specific antiserum E2 indicated that eledoisin-like peptide is not identical to eledoisin. Neurokinin A in carcinoid tumours has an N-terminal heterogeneity; this multiplicity constitutes a further support for the hypothesis that carcinoid tumours produce a number of tachykinins which may be present in different relative amounts in individual patients and may contribute to the individual differences in symptomatology.
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PMID:Isolation and characterization of neurokinin A, neurokinin A(3-10) and neurokinin A(4-10) from a neutral water extract of a metastatic ileal carcinoid tumour. 303 49

Angiotensin-converting enzyme was solubilized with papain from a particulate fraction of rat brain and purified to apparent homogeneity by a procedure including DEAE-cellulose, hydroxylapatite, Sephadex G-200, Cys(Bzl)-Pro-Sepharose, and ricin-Sepharose chromatography. Bradykinin potentiators, SQ 14,225, and Arg-Pro-Pro strongly inhibited the activity of the purified enzyme, whereas Phe-Ala, phosphoramidon, and pentobarbital exerted little inhibitory effect on the activity. Among neuropeptides investigated, substance P, bradykinin, and Leu-enkephalin (Arg6) exerted strong inhibitory actions on the enzyme. Furthermore, the latter two peptides were shown to be good substrates for the enzyme. Thus, angiotensin-converting enzyme of rat brain is distinct from endogenous enkephalinase and may interact with various neuropeptides located in the brain.
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PMID:Purification and inhibition by neuropeptides of angiotensin-converting enzyme from rat brain. 619 11

A substance P-hydrolyzing endopeptidase has been purified from a large quantity of human cerebrospinal fluid by ion exchange chromatography (DEAE-Sepharose CL-6B) and molecular sieving (Sephadex G-100 and Sephacryl S-200). The purification was monitored by measuring the conversion of synthetic substance P using a radioimmunoassay specific for its (1-7) fragment. The enzyme has an apparent molecular weight of 43,000. It cleaves predominantly at the Phe7-Phe8 and Phe8-Gly9 bonds but gives no or negligible conversion of the other tachykinins, neuromedin K and L (substance K).
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PMID:Characterization of substance P(1-7) and (1-8) generating enzyme in human cerebrospinal fluid. 621 84

1. A thiol proteinase from human pituitaries was purified approximately 400 fold and shown to have different chromatographic properties from that of calf brain. Among substrates cleaved were myelin basic protein, histones, beta-lipotropin, neurophysin, and Substance P. 2. The enzyme showed properties associated with a cathepsin-B like enzyme: dependence on -SH groups, pH optimum of 6.5, inhibition by leupeptin and a synthetic analog, Boc-D-Phe-Pro-arginal, and cleavage of dipeptidyl arylamides with basic residues adjacent to or penultimate to the chromatographic grouping. 3. Membranes present in the P2 fraction of rat brain contained three or more enkephalinases when submitted to DEAE-cellulose chromatography. Further purification on an IgG-Sepharose affinity column prepared with antibody to lung angiotensin converting enzyme indicated the presence of dipeptidyl carboxypeptidase(s) with properties distinct from those of ACE. In addition, the DEAE-cellulose fractions contained various aminopeptidase activities when tested with Leu-Gly-Gly, Leu-Nap, and Ala-Ala-Nap as substrates.
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PMID:Peptide processing in the central nervous system. 625 8


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