0000000000454961

AUTHOR

Patrice Boquet

showing 4 related works from this author

UDP-glucose deficiency in a mutant cell line protects against glucosyltransferase toxins from Clostridium difficile and Clostridium sordellii.

1996

Abstract We have previously isolated a fibroblast mutant cell with high resistance to the two Rho-modifying glucosyltransferase toxins A and B of Clostridium difficile. We demonstrate here a low level of UDP-glucose in the mutant, which explains its toxin resistance since: (i) to obtain a detectable toxin B-mediated Rho modification in lysates of mutant cells, addition of UDP-glucose was required, and it promoted the Rho modification dose-dependently; (ii) high pressure liquid chromatography analysis of nucleotide extracts of cells indicated that the level of UDP-glucose in the mutant (0.8 nmol/106 cells) was lower than in the wild type (3.7 nmol/106 cells); and (iii) sensitivity to toxin B…

Uridine Diphosphate GlucoseMicroinjectionsMutantBacterial ToxinsClostridium difficile toxin AClostridium sordelliiClostridium difficile toxin Bmedicine.disease_causeBiochemistryMicrobiologyCell LineCricetulusBacterial ProteinsGTP-Binding ProteinsCricetinaemedicineAnimalsMolecular BiologyClostridiumbiologyToxinClostridioides difficileWild typeCell BiologyClostridium difficilebiology.organism_classificationGlucosyltransferasesMutationbiology.proteinGlucosyltransferaseThe Journal of biological chemistry
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Large clostridial cytotoxins — a family of glycosyltransferases modifying small GTP-binding proteins

1996

Some Clostridium species produce AB x -type protein cytotoxins of high molecular weight. These toxins constitute the group of large clostridial cytotoxins (LCTs), which have homologous protein sequences, exert glycosyltransferase activity and modify GTP-binding proteins of the Ras-superfamily. These characteristics render the LCTs valuable tools for developmental and cell biologists.

ClostridiumMicrobiology (medical)Clostridium speciesMicrobial toxinsCytotoxinsBacterial ToxinsCellGlycosyltransferasesProtein superfamilyBiologyGlycosyltransferase activityMicrobiologyInfectious DiseasesGTP-binding protein regulatorsmedicine.anatomical_structureBiochemistryVirologyGlycosyltransferaseras Proteinsbiology.proteinmedicineCytotoxicityTrends in Microbiology
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Cytotoxic necrotizing factor type 2 produced by virulent Escherichia coli modifies the small GTP-binding proteins Rho involved in assembly of actin s…

1994

Cytotoxic necrotizing factor type 2 (CNF2) produced by Escherichia coli strains isolated from intestinal and extraintestinal infections is a dermonecrotic toxin of 110 kDa. We cloned the CNF2 gene from a large plasmid carried by an Escherichia coli strain isolated from a lamb with septicemia. Hydropathy analysis of the deduced amino acid sequence revealed a largely hydrophilic protein with two potential hydrophobic transmembrane domains. The N-terminal half of CNF2 showed striking homology (27% identity and 80% conserved residues) to the N-terminal portion of Pasteurella multocida toxin. Methylamine protection experiments and immunofluorescence studies suggested that CNF2 enters the cytosol…

rho GTP-Binding ProteinsBacterial ToxinsMolecular Sequence DataRestriction Mapping[SDV.BC]Life Sciences [q-bio]/Cellular BiologyBiologyIn Vitro TechniquesSEQUENCE GENIQUEmedicine.disease_causeCell LineGTP-binding protein regulatorsGTP-Binding ProteinsmedicineEscherichia coliHumansCloning MolecularCytoskeletonEscherichia coliPeptide sequence[SDV.BC] Life Sciences [q-bio]/Cellular BiologyActinAdenosine Diphosphate RiboseMultidisciplinaryBase SequenceSequence Homology Amino AcidCytotoxinsBinding proteinEscherichia coli ProteinsMolecular biologyActinsCytosolTransmembrane domainActin CytoskeletonBiochemistryGenes BacterialFACTEUR CYTOTOXIQUE NECROSANTSequence AlignmentResearch Article
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Ras, Rap, and Rac Small GTP-binding Proteins Are Targets for Clostridium sordellii Lethal Toxin Glucosylation

1996

Lethal toxin (LT) from Clostridium sordellii is one of the high molecular mass clostridial cytotoxins. On cultured cells, it causes a rounding of cell bodies and a disruption of actin stress fibers. We demonstrate that LT is a glucosyltransferase that uses UDP-Glc as a cofactor to covalently modify 21-kDa proteins both in vitro and in vivo. LT glucosylates Ras, Rap, and Rac. In Ras, threonine at position 35 was identified as the target amino acid glucosylated by LT. Other related members of the Ras GTPase superfamily, including RhoA, Cdc42, and Rab6, were not modified by LT. Incubation of serum-starved Swiss 3T3 cells with LT prevents the epidermal growth factor-induced phosphorylation of m…

ThreonineUridine Diphosphate GlucoseRHOABacterial ToxinsMolecular Sequence DataClostridium sordelliimacromolecular substancesCDC42GTPaseBiologyCell morphologyBiochemistryGTP PhosphohydrolasesProto-Oncogene Proteins p21(ras)MiceGTP-binding protein regulatorsGTP-Binding ProteinsAnimalsHumansAmino Acid SequenceMolecular BiologyClostridiumEpidermal Growth FactorKinase3T3 CellsCell Biologybiology.organism_classificationMolecular biologyActinsrac GTP-Binding ProteinsActin CytoskeletonKineticsGlucoserap GTP-Binding ProteinsGlucosyltransferasesCalcium-Calmodulin-Dependent Protein Kinasesbiology.proteinPhosphorylationGuanosine TriphosphateHeLa CellsJournal of Biological Chemistry
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