title: Characterization of the TolB-Pal trans-envelope complex from Xylella fastidiosa reveals a dynamic and coordinated protein expression profile during the biofilm development process.
abstract: The intriguing roles of the bacterial Tol-Pal trans-envelope protein complex range from maintenance of cell envelope integrity to potential participation in the process of cell division. In this study, we report the characterization of the XfTolB and XfPal proteins of the Tol-Pal complex of Xylella fastidiosa. X. fastidiosa is a major plant pathogen that forms biofilms inside xylem vessels, triggering the development of diseases in important cultivable plants around the word. Based on functional complementation experiments in Escherichia coli tolB and pal mutant strains, we confirmed the role of xftolB and xfpal in outer membrane integrity. In addition, we observed a dynamic and coordinated protein expression profile during the X. fastidiosa biofilm development process. Using small-angle X-ray scattering (SAXS), the low-resolution structure of the isolated XfTolB-XfPal complex in solution was solved for the first time. Finally, the localization of the XfTolB and XfPal polar ends was visualized via immunofluorescence labeling in vivo during bacterial cell growth. Our results highlight the major role of the components of the cell envelope, particularly the TolB-Pal complex, during the different phases of bacterial biofilm development.
authors.affiliation: Centro de Biologia Molecular e Engenharia Genética, Universidade Estadual de Campinas, Campinas, SP, Brazil.
authors.forename: Clelton A
authors.initials: CA
authors.lastname: Santos
authors.affiliation: Instituto de Fisica Gleb Wataghin, Universidade Estadual de Campinas, Campinas, SP, Brazil.
authors.forename: Richard
authors.initials: R
authors.lastname: Janissen
authors.affiliation: Centro de Biologia Molecular e Engenharia Genética, Universidade Estadual de Campinas, Campinas, SP, Brazil.
authors.forename: Marcelo A S
authors.initials: MA
authors.lastname: Toledo
authors.affiliation: Centro de Biologia Molecular e Engenharia Genética, Universidade Estadual de Campinas, Campinas, SP, Brazil.
authors.forename: Lilian L
authors.initials: LL
authors.lastname: Beloti
authors.affiliation: Departamento de Engenharia Química, Escola Politécnica, Universidade de São Paulo, São Paulo, SP, Brazil.
authors.forename: Adriano R
authors.initials: AR
authors.lastname: Azzoni
authors.affiliation: Instituto de Fisica Gleb Wataghin, Universidade Estadual de Campinas, Campinas, SP, Brazil.
authors.forename: Monica A
authors.initials: MA
authors.lastname: Cotta
authors.affiliation: Centro de Biologia Molecular e Engenharia Genética, Universidade Estadual de Campinas, Campinas, SP, Brazil; Departamento de Biologia Vegetal, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brazil. Electronic address: anete@unicamp.br.
authors.forename: Anete P
authors.initials: AP
authors.lastname: Souza
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D018441:Biofilms / Q000254:growth & development*; D002462:Cell Membrane / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D002473:Cell Wall / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D005816:Genetic Complementation Test; D008074:Lipoproteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D008958:Models, Molecular; D010457:Peptidoglycan / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D033903:Periplasmic Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D053838:Scattering, Small Angle; D017386:Sequence Homology, Amino Acid; D014961:X-Ray Diffraction; D044167:Xylella / Q000235:genetics* / Q000378:metabolism / Q000648:ultrastructure
chemical_list: D001425:Bacterial Outer Membrane Proteins; D029968:Escherichia coli Proteins; C031163:ExcC protein, E coli; D008074:Lipoproteins; D010457:Peptidoglycan; D033903:Periplasmic Proteins; D011994:Recombinant Proteins; C062094:tolB protein, E coli
keywords: Biofilm; Cell-envelope; Pathogenicity; TolB-Pal complex; Xylella fastidiosa