Nanowire arrays as cell force sensors to investigate adhesin-enhanced holdfast of single cell bacteria and biofilm stability

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORSurface attachment of a planktonic bacteria, mediated by adhesins and extracellular polymeric substances (EPS), is a crucial step for biofilm formation. Some pathogens can modulate cell adhesiveness, impacting host colonization and virulence. A framework able to quantify cell-surface interaction forces and their dependence on chemical surface composition may unveil adhesiveness control mechanisms as new targets for intervention and disease control. Here we employed InP nanowire arrays to dissect factors involved in the early stage biofilm formation of the phytopathogen Xylella fastidiosa. Ex vivo experiments demonstrate single-cell adhesion forces up to 45 nN, depending on the cell orientation with respect to the surface. Larger adhesion forces occur at the cell poles; secreted EPS layers and filaments provide additional mechanical support. Significant adhesion force enhancements were observed for single cells anchoring a biofilm and particularly on XadA1 adhesincoated surfaces, evidencing molecular mechanisms developed by bacterial pathogens to create a stronger holdfast to specific host tissues.Surface attachment of a planktonic bacteria, mediated by adhesins and extracellular polymeric substances (EPS), is a crucial step for biofilm formation. Some pathogens can modulate cell adhesiveness, impacting host colonization and virulence. A framework able to quantify cell-surface interaction forces and their dependence on chemical surface composition may unveil adhesiveness control mechanisms as new targets for intervention and disease control. Here we employed InP nanowire arrays to dissect factors involved in the early stage biofilm formation of the phytopathogen Xylella fastidiosa. Ex vivo experiments demonstrate single-cell adhesion forces up to 45 nN, depending on the cell orientation with respect to the surface. Larger adhesion forces occur at the cell poles; secreted EPS layers and filaments provide additional mechanical support. Significant adhesion force enhancements were observed for single cells anchoring a biofilm and particularly on XadA1 adhesincoated surfaces, evidencing molecular mechanisms developed by bacterial pathogens to create a stronger holdfast to specific host tissues.Surface attachment of a planktonic bacteria, mediated by adhesins and extracellular polymeric substances (EPS), is a crucial step for biofilm formation. Some pathogens can modulate cell adhesiveness, impacting host colonization and virulence. A framework able to quantify cell-surface interaction forces and their dependence on chemical surface composition may unveil adhesiveness control mechanisms as new targets for intervention and disease control. Here we employed InP nanowire arrays to dissect factors involved in the early stage biofilm formation of the phytopathogen Xylella fastidiosa. Ex vivo experiments demonstrate single-cell adhesion forces up to 45 nN, depending on the cell orientation with respect to the surface. Larger adhesion forces occur at the cell poles; secreted EPS layers and filaments provide additional mechanical support. Significant adhesion force enhancements were observed for single cells anchoring a biofilm and particularly on XadA1 adhesincoated surfaces, evidencing molecular mechanisms developed by bacterial pathogens to create a stronger holdfast to specific host tissues.16746564664FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR08/57906-3; 2010/51748-7; 2013/02300-1573913/2008-0; 479486/2012-3Sem informaçãoThe authors acknowledge J. H. Clerici, V. B. Pelegati, and M. O. Baratti for technical assistance and C. B. Santos and Prof. A. P. de Souza, from CBMEG/UNICAMP for providing the XadA1 protein. A.C. and E.P.A.M.B. would like to acknowledge Rene Van Veldhoven for the exceptional work and care for the MOVPE systems and the technical support from the Nano-Lab@TU/e cleanroom. This work was financially supported by FAPESP (Fundacao de Amparo a Pesquisa do Estado de Sao Paulo, Brazil), through grants 2010/51748-7 and 2013/02300-1, and CNPq (Conselho Nacional de Desenvolvimento Cientifico e Tecnologico, Brazil), grant number 479486/2012-3. D.M.M. and M.P.M. acknowledge scholarships from CAPES (Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior, Brazil); P.K.S. and R.J. acknowledge FAPESP for funding their scholarships. M.A.C., A.A.S., and H.F.C. acknowledge CNPq fellowships. The authors thank the access to confocal microscopy equipment provided by the National Institute of Science and Technology on Photonics Applied to Cell Biology (INFABIC) at the State University of Campinas; INFABIC is cofunded by FAPESP (08/57906-3) and CNPq (573913/2008-0). We also acknowledge the National Nano technology Laboratory (LNNano) at CNPEM, Brazil, for granting access to their electron microscopy facilities. A.C. and E.P.A.M.B. acknowledge the funding of the Dutch Technology Foundation STW (Project 11826), which is part of The Netherlands Organisation for Scientific Research (NWO), and which is partly funded by the Dutch Ministry of Economic Affairs