Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0043167 (pertussis)
 19,595 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Corticostatic peptides are a family of arginine-rich cysteine-rich peptides that inhibit ACTH-stimulated corticosterone (B) production in rat adrenal cell suspensions. In this communication we describe a new method for the facile isolation and purification of these basic peptides from rabbit adult lung. We then describe the isolation and sequences of the four rabbit peptides, CSI, CSII, CSIII, and CSIV, and compare their biological activities in the ACTH (150 pg/ml) inhibition assay. CSI is by far the most potent of the four peptides. Using CSI as a model, we then studied its effects on the proximal and distal parts of the pathway leading to the generation of cAMP. CSI had no effect on (Bu)2cAMP action on forskolin or cholera toxin in their ability to mimic ACTH and increase B production in rat adrenal cells, nor did CSI have any effect on the stimulation of B production by pertussis toxin. Endogenous cAMP stimulated by ACTH decreased after the addition of CSI, which pointed to the inhibition of ACTH binding to explain the mode of action of this corticostatin. Displacement of the specific binding of labeled ACTH by CSI and the ACTH antagonist ACTH-(6-24) was determined, and indeed, CSI did displace ACTH from its binding site. The question of what portion of the ACTH molecule was involved in the action of CSI was answered by studying ACTH-(1-13) acetyl amide (alpha MSH) and ACTH-(1-18) amide. CSI had no effect on alpha MSH stimulation of B production, but did lower the production of B stimulated by ACTH-(1-18) amide. Therefore, CSI must act on ACTH-(14-18), which is part of the so-called address region of ACTH, which is -Gly14-Lys15-Lys16-Arg17-Arg18-, the very basic part of the molecule. These results indicate that CSI acts by competing with ACTH for its binding receptor on the adrenal cell and that this competition is confined to amino acids 14-18 of the molecule when it is bound to the receptor.
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PMID:Isolation and mode of action of rabbit corticostatic (antiadrenocorticotropin) peptides. 131 Dec 40

The sulfhydryl alkylating agent N-ethylmaleimide (NEM) was used to probe the possible modulation of calcium current (ICa) by G-proteins in identified neurons of Aplysia californica. ICa recorded with conventional two-electrode voltage clamp was irreversibly suppressed by bath applied NEM in a concentration-dependent manner. This effect was fully blocked by addition of dithiothreitol or intracellular pressure injection of GTP gamma S but was unaffected by pre-treatment with pertussis toxin. These findings suggest that NEM inhibits ICa by causing persistent activation of an inhibitory G-protein in the absence of applied agonist. It appears that alkylation of key cysteine residues involved in G-protein deactivation underlie this effect.
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PMID:An N-ethylmaleimide-sensitive G-protein modulates Aplysia Ca2+ channels. 133 63

Nitric oxide-releasing compounds were shown to activate an ADP-ribosyltransferase activity in the cytosol of Dictyostelium discoideum. The enzyme ADP-ribosylated a cytosolic protein of approximately 41 kDa, p41. Neither cGMP nor GTP and its analogues affected this ADP-ribosylation. p41 differs from other substrates ADP-ribosylated by cholera, pertussis, or diphtheria toxins. Treatment of ADP-ribosylated p41 with snake venom phosphodiesterase released adenosine 5'-monophosphate, indicating a mono-ADP-ribose-protein linkage. This linkage was stable to neutral hydroxylamine but was sensitive to mercury ions and iodomethane, suggesting an attachment to a cysteine residue. Treatment of intact cells with nitric oxide-releasing compounds appeared to stimulate the ADP-ribosylation of p41 and this modification was reversible.
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PMID:Nitric oxide stimulates the ADP-ribosylation of a 41-kDa cytosolic protein in Dictyostelium discoideum. 135 80

ADP-ribosylation is a posttranslational modification of proteins by amino acid-specific ADP-ribosyltransferases. Both pertussis toxin and eukaryotic enzymes ADP-ribosylate cysteine residues in proteins and also, it has been suggested, free cysteine. Analysis of the reaction mechanisms of cysteine-specific ADP-ribosyltransferases revealed that free ADP-ribose combined nonenzymatically with cysteine. L- and D-cysteine, L-cysteine methyl ester, and cysteamine reacted with ADP-ribose, but alanine, serine, lysine, arginine, N-acetyl-L-cysteine, 2-mercaptoethanol, dithiothreitol, and glutathione did not. The 1H NMR spectrum of the product, along with the requirement for both free sulfhydryl and amino groups of cysteine, suggested that the reaction produced a thiazolidine linkage. ADP-ribosylthiazolidine was labile to hydroxylamine and mercuric ion, unlike the ADP-ribosylcysteine formed by pertussis toxin and NAD in guanine nucleotide-binding (G-) proteins, which is labile to mercuric ion but stable in hydroxylamine. In the absence of G-proteins but in the presence of NAD and cysteine, pertussis toxin generated a hydroxylamine-sensitive product, suggesting that a free ADP-ribose intermediate, expected to be formed by the NADase activity of the toxin, reacted with cysteine. Chemical analysis, or the use of alternative thiol acceptors lacking a free amine, is necessary to distinguish the enzymatic formation of ADP-ribosylcysteine from nonenzymatic formation of ADP-ribosylthiazolidine, thereby differentiating putative NAD:cysteine ADP-ribosyltransferases from NAD glycohydrolases.
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PMID:Amino acid-specific ADP-ribosylation: structural characterization and chemical differentiation of ADP-ribose-cysteine adducts formed nonenzymatically and in a pertussis toxin-catalyzed reaction. 144 18

Starfish-oocyte maturation induced by 1-methyladenine (MeAde) was inhibited by microinjection of pertussis toxin (PTX). The inhibition appeared to result from PTX-catalyzed ADP-ribosylation of a 39-kDa guanosine-nucleotide-binding regulatory protein (G protein) in the oocyte. These results strongly support the hypothesis that the MeAde-induced signals operate via a membrane receptor and are carried by the PTX-sensitive G protein. When PTX-injected oocytes were treated with dithiothreitol, 85% of them reinitiated meiosis, suggesting that dithiothreitol did not act on the MeAde receptor. We constructed a cDNA library from the immature ovary of starfish, Asterina pectinifera, and screened it with the cDNA of the alpha subunit of an inhibitory rat G protein (Gi-2). A positive cDNA clone contained an open reading frame of 1062 bases which had 74% identity with the rat Gi-2 cDNA. The deduced amino acid sequence was 85% and 89% identical to rat Gi-2 and rat Gi-1, respectively. The alpha subunit of the G protein purified from cortices of starfish oocytes was digested by trypsin and the resulting four peptides were microsequenced. Comparison of these amino acid sequences with the predicted one indicated that the isolated cDNA clone encoded the alpha subunit of the PTX-sensitive G protein in oocytes. The C-terminal sequence, KNNLKDCGLF, was identical to that of Gi, suggesting that the cysteine residue is the site of ADP-ribosylation.
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PMID:The primary structure of the alpha subunit of a starfish guanosine-nucleotide-binding regulatory protein involved in 1-methyladenine-induced oocyte maturation. 149 60

The guanine nucleotide-binding protein G(o alpha) has been implicated in the regulation of Ca2+ channels in neural tissues. Covalent modification of G(o alpha) by pertussis toxin-catalyzed ADP-ribosylation of a cysteine (position 351) four amino acids from the carboxyl terminus decouples G(o alpha) from receptor. To define the structural requirements for ADP-ribosylation, preparations of recombinant G(o alpha) with mutations within the five amino acids at the carboxyl terminus were evaluated for their ability to serve as pertussis toxin substrates. As expected, the mutant in which cysteine 351 was replaced by glycine (C351G) was not a toxin substrate. Other inactive mutants were G352D and L353 delta/Y354 delta. Mutations that had no significant effect on toxin-catalyzed ADP-ribosylation included G350D, G350R, Y354 delta, and L353V/Y354 delta. Less active mutants were L353G/Y354 delta, L353A/Y354 delta, and L353G. ADP-ribosylation of the active mutants, like that of wild-type G(o alpha), was enhanced by the beta gamma subunits of bovine transducin. It appears that three of the four terminal amino acids critically influence pertussis toxin-catalyzed ADP-ribosylation of G(o alpha).
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PMID:Pertussis toxin-catalyzed ADP-ribosylation of G(o) alpha with mutations at the carboxyl terminus. 151 Sep 59

Transducin, the signal coupling protein of retinal rod photoreceptor cells, is one of a family of G proteins that can be inactivated by pertussis toxin. We have investigated the nature of this inactivation in order to determine (1) whether it requires the toxin-catalyzed transfer of ADP-ribose from NAD+ to cysteine-347 of the alpha subunit and (2) whether it involves locking the alpha subunit in the inactive conformation characteristic of its GDP-bound state, or is limited to disruption of binding to photoexcited rhodopsin (R*). Our results indicate that all observed effects of pertussis toxin treatment, including a shift in the electrophoretic mobility of transducin's alpha subunit and functional inactivation, require NAD+ and that the appearance of the shift parallels incorporation of ADP-ribose. We have also found that, apart from interactions with photoexcited rhodopsin, the functional properties of ADP-ribosylated transducin are essentially the same as those of unmodified transducin. Normal spontaneous nucleotide exchange kinetics and the ability to activate cGMP phosphodiesterase are preserved following quantitative ADP-ribosylation, as are the abilities to hydrolyze GTP, to bind to a dye affinity column, and to display enhanced fluorescence upon addition of Al3+ and F-. Thus, ADP-ribosylation merely blocks catalysis of transducin nucleotide exchange by R* and does not lock transducin in an inactive state.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Nucleotide exchange and cGMP phosphodiesterase activation by pertussis toxin inactivated transducin. 166 Nov 43

3H-Labelled kappa-elastin peptides (kE:75 kDa molecular weight) were shown to bind to confluent human skin fibroblast (HSF) cultures in a time-dependent and saturable manner. Scatchard analysis indicated the presence of high affinity binding sites with kD = 2.7 x 10(-10) M and 19,000 sites per cell. Binding of kE to its receptor on HSF accelerates and intensifies the adhesion of insoluble elastin fibres (iE) to confluent HSF. Optimal effect was attained for a kE concentration of 0.3 x 10(-9) M close to kD. This stimulatory effect of kE on the binding of iE to HSF could be inhibited by neomycin, retinal and pertussis toxin, substances which act at different levels of the transduction mechanism following the activation of the receptor and the subsequent triggering of cell biological events (chemotaxis, modification of calcium fluxes). The stimulation of iE adhesion to HSF induced by kE as well as kE binding to the cells could be inhibited by lactose and laminin but not by Arg-Gly-Asp-Ser(RGDS) peptides. This indicates that the elastin peptide receptor on HSF possesses lectin-like properties and shares homology with the laminin receptor as also shown for other cell types. None of the substances tested, that is inhibitors of the transduction mechanism, lactose, laminin and Arg-Gly-Asp-Ser(RGDS) peptides were shown to interfere significantly with the binding of iE (in the absence of added kE) to confluent HSF. The proteins adhering strongly to elastin fibres were isolated by a sequential extraction procedure and the final hydrochloride guanidinium-DTT extract was analysed by SDS-PAGE under reducing conditions, Western blots using specific antibodies against several connective tissue proteins and affinity for [3H]-kE following nitrocellulose electro-transfer of proteins. Fibronectin, vitronectin, tropoelastin(s), and a 120 kDa cysteine rich glycoprotein previously designated as elastonectin were identified. Among these proteins, [3H]-kE was found to bind exclusively to a 65 kDa protein that could be eluted selectively from elastin fibres with a neutral buffer containing 100 mM lactose. Therefore the elastin peptide receptor on human skin fibroblasts shares properties with the elastin receptor characterized from other cell types. Conformational differences between elastin peptides and elastin fibres could explain the differences in the mechanisms of interactions between elastin fibres and elastin peptides with HSF in culture. The stimulatory effect of elastin-derived peptides on the adhesion of elastin fibres to HSF could have implications in the oriented biosynthesis of elastin fibres.
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PMID:Mechanisms of interaction between human skin fibroblasts and elastin: differences between elastin fibres and derived peptides. 172 59

Certain microbial toxins are ADP-ribosyltransferases, acting on specific substrate proteins. Although these toxins have been of great utility in studies of cellular regulatory processes, a simple procedure to directly study toxin-catalyzed ADP-ribosylation in intact cells has not been described. Our approach was to use [2-3H]adenine to metabolically label the cellular NAD+ pool. Labeled proteins were then denatured with SDS, resolved by PAGE, and detected by flurography. In this manner, we show that pertussis toxin, after a dose-dependent lag period, [3H]-labeled a 40-kD protein intact cells. Furthermore, incubation of the gel with trichloroacetic acid at 95 degrees C before fluorography caused the release of label from bands other than the pertussis toxin substrate, thus, allowing its selective visualization. The modification of the 40-kD protein was ascribed to ADP-ribosylation of a cysteine residue on the basis of inhibition of labeling by nicotinamide and the release of [3H]ADP-ribose from the labeled protein by mercuric acetate. Cholera toxin catalyzed the [3H]-labeling of a 46-kD protein in the [2-3H]adenine-labeled cells. Pretreatment of the cells with pertussis toxin before the labeling of NAD+ with [2-3H]adenine blocked [2-3H]ADP-ribosylation catalyzed by pertussis toxin, but not that by cholera toxin. Thus, labeling with [2-3H]adenine permits the study of toxin-catalyzed ADP-ribosylation in intact cells. Pasteurella multocida toxin has recently been described as a novel and potent mitogen for Swiss 3T3 cell and acts to stimulate the phospholipase C-mediated hydrolysis of polyphosphoinositides. The basis of the action of the toxin is not known. Using the methodology described here, P. multocida toxin was not found to act by ADP-ribosylation.
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PMID:A novel approach to detect toxin-catalyzed ADP-ribosylation in intact cells: its use to study the action of Pasteurella multocida toxin. 183 59

The outer membrane of Wolinella recta ATCC 33238 was isolated by French pressure cell disruption and differential centrifugation. Outer membrane proteins (OMPs) were solubilized by Zwittergent 3.14 extraction and separated by DEAE-Sephacel ion-exchange chromatography. The major OMPs that were found in W. recta ATCC 33238 and in several other Wolinella spp. consisted of proteins with apparent molecular masses of 51, 45, and 43 kDa. These three conserved proteins were purified to essential homogeneity by one- and two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and characterized chemically. Heating at between 75 and 100 degrees C revealed both the 43- and 51-kDa proteins to be heat modified from apparent molecular masses of 32 and 38 kDa, respectively. The 45-kDa protein was unmodified at all temperatures tested. Two-dimensional isoelectric focusing-SDS-PAGE revealed the 51-kDa protein to be composed of multiple pIs between a pH of 5.0 and greater than 8.0 while the 43- and 45-kDa proteins had a pI of approximately 6.0. N'-terminal amino acid sequence analysis of the first 30 to 40 amino acids and search of the Protein Identification Resource data base for similar proteins only revealed the 43-kDa protein to be similar to the P.69 OMP of Bordetella pertussis; however, the homology was weak (33%). Amino acid analysis revealed the 43-kDa protein to be noncharged and the 45- and 51-kDa proteins to be hydrophilic, containing between 38 to 42% polar residues but no cysteine. This study reports the purification and partial characterization of three conserved proteins in W. recta ATCC 33238.
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PMID:Extraction, purification, and characterization of major outer membrane proteins from Wolinella recta ATCC 33238. 189 72


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