title: The Secreted Protease PrtA Controls Cell Growth, Biofilm Formation and Pathogenicity in Xylella fastidiosa.
abstract: Pierce's disease (PD) is a deadly disease of grapevines caused by the Gram-negative bacterium Xylella fastidiosa. Though disease symptoms were formerly attributed to bacteria blocking the plant xylem, this hypothesis is at best overly simplistic. Recently, we used a proteomic approach to characterize the secretome of X. fastidiosa, both in vitro and in planta, and identified LesA as one of the pathogenicity factors of X. fastidiosa in grapevines that leads to leaf scorching and chlorosis. Herein, we characterize another such factor encoded by PD0956, designated as an antivirulence secreted protease "PrtA" that displays a central role in controlling in vitro cell proliferation, length, motility, biofilm formation, and in planta virulence. The mutant in X. fastidiosa exhibited reduced cell length, hypermotility (and subsequent lack of biofilm formation) and hypervirulence in grapevines. These findings are supported by transcriptomic and proteomic analyses with corresponding plant infection data. Of particular interest, is the hypervirulent response in grapevines observed when X. fastidiosa is disrupted for production of PrtA, and that PD-model tobacco plants transformed to express PrtA exhibited decreased symptoms after infection by X. fastidiosa.
authors: Plant Sciences Department, University of California, Davis, CA, USA.
authors: Hossein
authors: H
authors: Gouran
authors: Plant Sciences Department, University of California, Davis, CA, USA.
authors: Hyrum
authors: H
authors: Gillespie
authors: Plant Sciences Department, University of California, Davis, CA, USA.|Institute of Genetics and Biochemistry, Federal University of Uberlândia, Brazil.
authors: Rafael
authors: R
authors: Nascimento
authors: Plant Sciences Department, University of California, Davis, CA, USA.
authors: Sandeep
authors: S
authors: Chakraborty
authors: Institute of Genetics and Biochemistry, Federal University of Uberlândia, Brazil.
authors: Paulo A
authors: PA
authors: Zaini
authors: Plant Sciences Department, University of California, Davis, CA, USA.
authors: Aaron
authors: A
authors: Jacobson
authors: Proteomics Core, Genome Center, University of California, Davis, USA.
authors: Brett S
authors: BS
authors: Phinney
authors: Plant Sciences Department, University of California, Davis, CA, USA.
authors: David
authors: D
authors: Dolan
authors: Public Health Sciences, University of California, Davis, USA.
authors: Blythe P
authors: BP
authors: Durbin-Johnson
authors: Plant and Microbial Biology Department, University of Berkeley, Berkeley, CA, USA.
authors: Elena S
authors: ES
authors: Antonova
authors: Plant and Microbial Biology Department, University of Berkeley, Berkeley, CA, USA.
authors: Steven E
authors: SE
authors: Lindow
authors: Surgical and Radiological Sciences, Vet Med, University of California, Davis, CA, USA.
authors: Matthew S
authors: MS
authors: Mellema
authors: Institute of Genetics and Biochemistry, Federal University of Uberlândia, Brazil.|Department of Medical Microbiology and Immunology, University of California, Davis, CA, USA.
authors: Luiz R
authors: LR
authors: Goulart
authors: Plant Sciences Department, University of California, Davis, CA, USA.
authors: Abhaya M
authors: AM
authors: Dandekar
mesh_terms: D018441:Biofilms / Q000254:growth & development*; D020869:Gene Expression Profiling; D055786:Gene Knockout Techniques; D008124:Locomotion; D008666:Metalloendopeptidases / Q000235:genetics / Q000378:metabolism*; D010935:Plant Diseases / Q000382:microbiology*; D040901:Proteomics; D014026:Nicotiana / Q000382:microbiology; D014774:Virulence; D027843:Vitis / Q000382:microbiology*; D044167:Xylella / Q000166:cytology / Q000235:genetics / Q000472:pathogenicity* / Q000502:physiology*
chemical_list: D008666:Metalloendopeptidases; C079508:PrtA metalloprotease