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Query: EC:2.4.2.30 (
PARP
)
13,611
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
An NAD:cysteine
ADP-ribosyltransferase
designated
ADP-ribosyltransferase
C was purified approximately 35,000-fold from human erythrocytes with an 11% yield. The purified
ADP-ribosyltransferase
C exhibited one predominant protein band on
sodium
dodecyl sulfate-polyacrylamide gels with an estimated molecular weight (Mr) of 28,500. The Km values for NAD and cysteine methyl ester were determined to be 65 and 4,400 microM, respectively. By using human erythrocyte inside-out membrane vesicles, the transferase C was found to ADP-ribosylate the alpha subunit (Mr = 41,000) of Gi, which is a substrate for pertussis toxin. The ADP-ribosylation of Gi alpha catalyzed by
ADP-ribosyltransferase
C was inhibited by pre-ADP-ribosylation with pertussis toxin. The linkage of ADP-ribose-Gi alpha in the membranes formed by
ADP-ribosyltransferase
C was as stable to hydroxylamine as that formed by pertussis toxin. These data represent the first demonstration that eukaryotic cells contain an
ADP-ribosyltransferase
which can catalyze the ADP-ribosylation of a cysteine residue in Gi alpha.
...
PMID:Eukaryotic mono(ADP-ribosyl)transferase that ADP-ribosylates GTP-binding regulatory Gi protein. 312 40
The
ADP-ribosyltransferase
activity of polypeptide A1 of cholera toxin and that of Escherichia coli heat-labile enterotoxin (LT) are primarily responsible for the toxic activities of these toxins. Since the amino acid sequences of the two A1 polypeptides are very similar, their functional mechanisms are considered to be the same. Arg-146 of polypeptide A1 is thought to be involved in the active site, because this amino acid of cholera toxin has been identified as the site of self-ADP-ribosylation. However, the exact role of Arg-146 and the significance of self-ADP-ribosylation in toxicity remain unclear. We substituted Arg-146 of polypeptide A1 of LT with Gly by oligonucleotide-directed mutagenesis and examined the biological property of the resultant mutant LT. The substitution changed the mobility of subunit A on
sodium
dodecyl sulfate-polyacrylamide gel but did not reduce the vascular permeability activity of LT. This result indicates that Arg-146 is not absolutely required for toxic activity and that LT can express its toxic activity without self-ADP-ribosylation at Arg-146.
...
PMID:Effect of substitution of glycine for arginine at position 146 of the A1 subunit on biological activity of Escherichia coli heat-labile enterotoxin. 312 2
The substrate for
ADP-ribosyltransferase
from Clostridium botulinum was purified from the cytosol of bovine adrenal gland. Purification procedures consisted of ammonium sulfate fractionation, chromatographies on columns of DEAE-Sepharose and phenyl-Sepharose, gel filtration on a TSK-gel G3000SW column, and Mono Q fast protein liquid chromatography. On DEAE-Sepharose chromatography, the substrate activity was eluted in two separate peaks, and electrophoretic analyses revealed that the substrates in the two peaks are of similar molecular weight but different isoelectric points. The major peak of the substrate was further purified. It was purified about 1,800-fold with a recovery of 2.2% by the above procedures. On
sodium
dodecyl sulfate-polyacrylamide gel electrophoresis, the final preparation showed a single protein band at Mr 22,000. The purified protein served as a substrate for botulinum
ADP-ribosyltransferase
and was maximally ADP-ribosylated to the extent of about 0.7 mol of ADP-ribose/mol of protein. A guanosine 5'-(3-O-thio)triphosphate (GTP gamma S) binding activity was co-purified with the ADP-ribosylation substrate, and the purified protein maximally bound about 0.5 mol of GTP gamma S/mol. GTP gamma S binding was effectively competed by GTP and GDP but not by GMP, ATP, and ADP. Thus, the ADP-ribosylation substrate is a GTP-binding protein. This protein, designated Gb (b for botulinum), is widely distributed in various tissues. It was rich in brain, pituitary, and adrenal glands, and poor in heart, smooth, and skeletal muscles.
...
PMID:Purification and properties of the cytosolic substrate for botulinum ADP-ribosyltransferase. Identification as an Mr 22,000 guanine nucleotide-binding protein. 313 28
ADP-ribosylation of arginine appears to be a reversible modification of proteins with NAD: arginine ADP-ribosyltransferases and ADP-ribosylarginine hydrolases catalyzing the opposing arms of the ADP-ribosylation cycle. ADP-ribosylarginine hydrolases have been purified extensively (greater than 90%) (150,000-250,000-fold) from the soluble fraction of turkey erythrocytes by DE-52, phenyl-Sepharose, hydroxylapatite, Ultrogel AcA 54, and Mono Q chromatography. Mobilities of the hydrolase on gel permeation columns and on
sodium
dodecyl sulfate-polyacrylamide gel electrophoresis under reducing conditions are consistent with an active monomeric species of approximately 39 kDa. Insertion of an organomercurial agarose chromatographic step prior to Ultrogel AcA 54 resulted in the isolation of a hydrolase exhibiting approximately 35-fold greater sensitivity to dithiothreitol (Ka,sensitive = 41 +/- 16.7 microM, n = 4; Ka,resistant = 1.44 +/- 0.12 mM, n = 3). A similar dithiothreitol-sensitive hydrolase was generated by exposure of the purified resistant enzyme to HgCl2. At 30 degrees C, both thiol-sensitive (HS) and thiol-resistant (HR) hydrolases were relatively resistant to N-ethylmaleimide (NEM); incubation with dithiothreitol prior to NEM resulted in complete inactivation. Both HS and HR required Mg2+ and thiol for enzymatic activity. Mg2+ stabilized both HS and HR against thermal inactivation in the absence and presence of thiol. A purified NAD:arginine
ADP-ribosyltransferase
, in the presence of NAD, inactivated both HS and HR; Mg2+ and to a greater extent Mg2+ plus dithiothreitol protected both HS and HR from NAD- and transferase-dependent inactivation. Thus, activation of the hydrolase enhanced its resistance to inactivation by transferase.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Purification and characterization of ADP-ribosylarginine hydrolase from turkey erythrocytes. 317 79
Synthetic and natural amphiphiles, octyl glucoside, Nonidet P40,
sodium
dodecyl sulfate (SDS), gangliosides GM1 and GD1a, interact with cholera toxin (CLT) and with its active region (promoter A). The formation of CLT-amphiphile complex leads to inhibition of
ADP-ribosyltransferase
activity, a characteristic of promoter A elicited after thiol-reagents treatment. In all cases the interaction produces the maximum inhibitory effect above the critical micellar concentration of amphiphiles, although monomers of SDS show inhibition activity as well. The gangliosides appear to be capable of altering bilayer organization of membrane, similar to synthetic detergents. When CLT-ganglioside complexes were incubated with cell culture medium containing 10% fetal calf serum (FCS) and
ADP-ribosyltransferase
activity was completely restored both in cholera toxin and in promoter A. Some protein of FCS, which is avid of gangliosides, seems to be responsible for reversibility of inhibition. The results indicate that the active site of promoter A may be located in a hydrophobic pocket of the toxin structure. Furthermore, CLT was bound to reconstituted Sendai virus envelopes (RSVEs), containing a small amount of GM1. The RSVEs are made of membranous vesicles, capable of binding and fusing with host cell membrane. The incubation for 1 1hr of RSVE bearing CLT with Friend's erythroleukemic cells produced the stimulation of adenylate cyclase. This stimulation appears to be due to the translocation of the active subunit of CLT in the inner half of plasma membrane.
...
PMID:Biological activity of preformed cholera toxin-ganglioside GM1 complex. 609 37
Cholera toxin catalyzed the ADP-ribosylation of the pituitary protein hormones thyrotropin (TSH), lutropin (LH), follitropin (FSH), human chorionic gonadotropin (hCG), and corticotropin (ACTH)1-24, and ADP-ribosylation of the basic proteins histone subfraction H1 and protamine. Casein and phosvitin, acidic nuclear proteins, did not act as acceptors for toxin-catalyzed ADP-ribosylation. The isolated TSH A and B subunits were tested for their ADP-ribose acceptor activity. The TSH A subunit showed fourfold greater ADP-ribose acceptor activity than the TSH B subunit. The ADP-ribose acceptor protein protamine was analyzed by
sodium
dodecyl sulfate polyacrylamide gel electrophoresis following incubation with cholera toxin under ADP-ribosylating conditions. [3H]ADP-ribose incorporated into protein from [3H]NAD migrated with the acceptor protein protamine. In the absence of added acceptor protein, the [3H]ADP-ribose incorporated into protein migrated with the A1 fragment of cholera toxin. Cholera toxin A and B subunits were isolated and tested for their ability to catalyze the transfer of ADP-ribose to protamine. The cholera toxin A subunit showed 50-fold greater
ADP-ribosyltransferase
activity than the B subunit. Our data indicate that a variety of adenohypophyseal hormones and regulatory proteins act as acceptors for toxin-catalyzed ADP-ribosylation. These studies may help in understanding the role of endogenous ADP-ribosyltransferases and the physiological effects of this modification of protein.
...
PMID:Polypeptide hormones and chromatin-associated proteins act as acceptors for cholera toxin-catalyzed ADP-ribosylation. 625 55
The activity of exotoxin A in culture filtrates prepared from cultures obtained by growing P. aeruginosa strains PA-7 and PA-103 in Martin's broth containing iron at a concentration of 0.08 microgram/ml, 0,05 M
sodium
glutamate and 1% of glycerin has been shown to be 1.5 times higher than that in filtrates prepared from cultures obtained by growing the above strains in a medium containing soybean tryptic digestion (USA). The optimun conditions for the production of exotoxin A by these strains are achieved during their cultivation in a fermenter at a temperature of 32 degrees C for 18 hours with simultaneous stirring (800 r. p. m.) and oxygenation (450 m3/h). Under these conditions the biological activity of the filtrates is 200 LD50/ml, their
ADP-ribosyltransferase
activity is 9500 c. p. m. and a sharply defined precipitation line appears in the double diffusion test in gel with monospecific antiserum to purified toxin, used in a dilution of 1:8.
...
PMID:[Exotoxin A production during Pseudomonas aeruginosa PA-7 cultivation in Martin's broth]. 633 Oct 28
Poly(ADP-ribose) glycohydrolase has been purified about 12 300-fold from pig thymus with a recovery of 8.5%. The specific activity of the purified enzyme is 13.8 mumol min -1 mg protein -1. The molecular weight was estimated to be 59 000 by gel filtration through Sephadex G-100 in a non-denaturing solvent. Analysis of the final preparation by
sodium
dodecyl sulphate gel electrophoresis reveals two protein bands of molecular weight, 61 500 and 67 500. The Km value for poly(ADP-ribose) is estimated to be 1.8 microM monomer units. The enzyme preparation is free from phosphodiesterase, NADase and
ADP-ribosyltransferase
activities. The purified enzyme is inhibited by cyclic AMP, ADP-ribose, naphthylamine, histones H1, H2A, H2B, H3, polylysine, polyarginine, polyornithine and protamine. The inhibition by histone is relieved by an equal mass of DNA. Single-stranded DNA, poly(A), poly(I) and polyvinyl sulphate were inhibitory, but double-stranded DNA was not inhibitory.
...
PMID:Isolation and purification of poly(ADP-ribose) glycohydrolase from pig thymus. 661 43
When isolated myelin membranes were ADP-ribosylated by [32P]NAD+ either in the absence of toxin (by the membrane
ADP-ribosyltransferase
) or in the presence of cholera toxin, the same proteins were ADP-ribosylated in both cases and myelin basic protein (MBP) was the major radioactive product. Therefore, cholera toxin was considered a good model for ADP-ribosylation of myelin proteins. Although purified human MBP migrates as a single band on
sodium
dodecyl sulfate-polyacrylamide gel electrophoresis with a molecular mass of 20 kDa, the microheterogeneity that is masked under these conditions can be clearly demonstrated on alkaline-urea gels at pH 10.6. At this pH, MBP is resolved into several components that differ one from the other by a single charge (charge isomers). These charge isomers can be resolved on CM52 columns at pH 10.6, and several can be ADP-ribosylated. Component 1 (C-1), the most cationic charge isomer, incorporated 1.79 mol of ADP-ribose/mol of protein. C-2 and C-3 (which differ from C-1 by the loss of one and two positive charges, respectively) incorporated slightly less at 1.67 and 1.63 mol of ADP-ribose/mol of protein, respectively, whereas C-8, the least cationic, incorporated less than 0.11 mol/mol of protein. In the presence of neutral hydroxylamine, the ADP-ribosyl bond was shown to have a half-life of about 80 min, suggesting an N-glycosidic linkage between ADP-ribose and an arginyl residue of the protein.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:ADP-ribosylation of human myelin basic protein. 751 50
The structural gene for the 49-kDa form of exoenzyme S (exoS) isolated from Pseudomonas aeruginosa 388 was expressed in both Escherichia coli and P. aeruginosa PA103. Expression of exoS in E. coli under the transcriptional regulation of the T7 promoter yielded a soluble cytosolic protein with an apparent molecular mass of 49 kDa, as determined by
sodium
dodecyl sulfate-polyacrylamide gel electrophoresis. Expression of exoS in P. aeruginosa PA103 under the transcriptional regulation of the 0.9 kbp of Pseudomonas chromosomal DNA flanking the 5' end of exoS yielded a nitrilotriacetic acid-inducible extracellular protein with an apparent molecular mass of 49 kDa. Recombinant ExoS (rExoS) reacted with the anti-49-kDa form of exoenzyme S immunoglobulin G, existed as an aggregate as determined by gel filtration chromatography, and ADP-ribosylated soybean trypsin inhibitor at a specific activity that was similar (within twofold) to that of native exoenzyme S. Allelic exchange of exoS with a tetracycline gene cartridge yielded a strain of P. aeruginosa 388 that did not express detectable amounts of either ExoS in an immunoblot analysis using the anti-49-kDa form of exoenzyme S immunoglobulin G or
ADP-ribosyltransferase
activity under standard enzyme assay conditions. Expression of catalytically active rExoS in E. coli demonstrated that exoS was necessary and sufficient for the factor-activating exoenzyme S-dependent
ADP-ribosyltransferase
activity of exoenzyme S. Expression of nitrilotriacetic acid-inducible rExoS in P. aeruginosa PA103 demonstrated that the 0.9 kbp of Pseudomonas chromosomal DNA flanking the 5' end of exoS encoded a functional exoenzyme S promoter. Expression analysis and allelic exchange experiments suggest that the 49- and 53-kDa forms of exoenzyme S are encoded by separate genes.
...
PMID:Expression of recombinant exoenzyme S of Pseudomonas aeruginosa. 780 44
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