En savoir plus

Abstract

The plant-pathogenic bacterium X. campestris pv. vesicatoria utilizes a type III secretion (T3S) system to translocate effector proteins into plant cells. The T3S system is a molecular nanomachine which spans both bacterial membranes and is associated with an extracellular pilus and a channel-like translocon in the host plasma membrane. T3S substrates contain an N-terminal secretion signal which is not conserved on the amino acid level and is presumably recognized by components of the secretion apparatus. We localized T3S and translocation signals in T3S substrates from X. campestris pv. vesicatoria. Secretion and translocation assays with deletion derivatives of secreted proteins and reporter fusion proteins revealed that the export signal is usually localized within the N-terminal 40 to 50 amino acids of T3S substrates. In case of the predicted inner rod protein HrpB2, experimental evidence suggests that the T3S signal contributes to the docking of HrpB2 to components of the T3S system and determines the secretion specificity. We show that the export signal of HrpB2 can efficiently target reporter proteins for translocation in the absence of the control proteins HpaB and HpaC.

En savoir plus

• Structure de rattachement et adresse professionnelle : Institute of Biology, Dept. of Genetics, Martin-Luther University Halle-Wittenberg
• Page personnelle : http://www.biologie.uni-halle.de/institutsbereich_genetik/plant_genetics/pd_dr._daniela_buettner_/
• Courriel : daniela.buettner@genetik.uni-halle.de

Contact

Fabienne Vailleau >>>