title: Localization and characterization of Xylella fastidiosa haemagglutinin adhesins.
abstract: Xylella fastidiosa is a gram-negative, xylem-inhabiting, plant-pathogenic bacterium responsible for several important diseases including Pierce's disease (PD) of grapevines. The bacteria form biofilms in grapevine xylem that contribute to the occlusion of the xylem vessels. X. fastidiosa haemagglutinin (HA) proteins are large afimbrial adhesins that have been shown to be crucial for biofilm formation. Little is known about the mechanism of X. fastidiosa HA-mediated cell-cell aggregation or the localization of the adhesins on the cell. We generated anti-HA antibodies and show that X. fastidiosa HAs are present in the outer membrane and secreted both as soluble proteins and in membrane vesicles. Furthermore, the HA pre-proteins are processed from the predicted molecular mass of 360 kDa to a mature 220 kDa protein. Based on this information, we are evaluating a novel form of potential resistance against PD by generating HA-expressing transgenic grapevines.
authors.affiliation: Department of Plant Pathology, University of California, Davis, CA 951616, USA.|Center for Applied Biosciences, University of Freiburg, Germany.
authors.forename: Tanja M
authors.initials: TM
authors.lastname: Voegel
authors.affiliation: Department of Plant Pathology, University of California, Davis, CA 951616, USA.
authors.forename: Jeremy G
authors.initials: JG
authors.lastname: Warren
authors.affiliation: Department of Microbiology, University of California, Davis, CA 951616, USA.
authors.forename: Ayumi
authors.initials: A
authors.lastname: Matsumoto
authors.affiliation: Department of Microbiology, University of California, Davis, CA 951616, USA.
authors.forename: Michele M
authors.initials: MM
authors.lastname: Igo
authors.affiliation: Department of Plant Pathology, University of California, Davis, CA 951616, USA.
authors.forename: Bruce C
authors.initials: BC
authors.lastname: Kirkpatrick
mesh_terms: D018829:Adhesins, Bacterial / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D018441:Biofilms; D006388:Hemagglutinins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008970:Molecular Weight; D021381:Protein Transport; D044167:Xylella / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D018829:Adhesins, Bacterial; D001425:Bacterial Outer Membrane Proteins; D006388:Hemagglutinins