Détermination structurale de la cassiicoline, la toxine glycosylée de Corynespora cassiicola

Corynespora cassiicola est un champignon phytopathogène nécrotrophe capable d'infecter plus de 70 plantes hôtes, parmi lesquelles, la tomate, le concombre, le coton, le soja ou l'hévéa. Dans le cas de l'hévéa, la pathologie induite par C.!cassiicola se manifeste par des défoliations massives pouvant conduire à la mort de l'arbre. Cette infection est en constante progression dans toutes les zones de production

Letter to the Editor: 1 H, 15 N and 13 C chemical shift assignments of the Pleckstrin Homology domain of the Human Protein Kinase B (PKB/Akt)

International audienc

Solution Structure of Human p8 MTCP1 , a Cysteine-rich Protein Encoded by the MTCP1 Oncogene, Reveals a New a a a-Helical Assembly Motif

International audienceMature-T-Cell Proliferation) is the ®rst gene unequivocally identi®ed in the group of uncommon leukemias with a mature phenotype. The three-dimensional solution structure of the human p8 MTCP1 protein encoded by the MTCP1 oncogene was determined by homonuc-lear proton two-dimensional NMR methods at 600 MHz. After sequence speci®c assignments, a total of 931 distance restraints and 57 dihedral restraints were collected. The location of the three previously unassigned disul®de bridges was determined from preliminary DIANA structures, using a statistical analysis of intercystinyl distances. The solution structure of p8 MTCP1 is presented as a set of 30 DIANA structures, further re®ned by restrained molecular dynamics using a simulated annealing protocol with the AMBER force ®eld. The r.m.s.d. values with respect to the mean structure for the backbone and all heavy atoms for a family of 30 structures are 0.73(AE0.28) and 1.17(AE0.23) A Ê , when the structured core of the protein (residues 5 to 63) is considered. The solution structure of p8 MTCP1 reveals an original scaffold consisting of three a helices, associated with a new cysteine motif. Two of the helices are covalently paired by two disul®de bridges, forming an a-hairpin which resembles an antiparallel coiled-coil. The third helix is oriented roughly parallel to the plane de®ned by the a-antiparallel motif and its axis forms an angle of %60 with respect to the main axis of this motif

The structure of a resuscitation-promoting factor domain from Mycobacterium tuberculosis shows homology to lysozymes

Resuscitation-promoting factor (RPF) proteins reactivate stationary-phase cultures of (G+C)-rich Gram-positive bacteria including the causative agent of tuberculosis, Mycobacterium tuberculosis. We report the solution structure of the RPF domain from M. tuberculosis Rv1009 (RpfB) solved by heteronuclear multidimensional NMR. Structural homology with various glycoside hydrolases suggested that RpfB cleaved oligosaccharides. Biochemical studies indicate that a conserved active site glutamate is important for resuscitation activity. These data, as well as the presence of a clear binding pocket for a large molecule, indicate that oligosaccharide cleavage is probably the signal for revival from dormancy

Capture in the metabolic arena: co-selection of gamma and deltaretrovirus envelope glycoproteins and their receptors

International audiencen.