ICT - MILSTEIN   05483
INSTITUTO DE CIENCIA Y TECNOLOGIA "DR. CESAR MILSTEIN"
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
A role for the type II secretion system in biofilm formation in Xanthomonas axonopodis pv citri (Xac)
Autor/es:
RAFAEL A HOMMEM; FLORENCIA MALAMUD; ADRIAN A VOJNOV; MARCOS A MACHADO; ALEXANDRE M DO AMARAL
Lugar:
Villa Carlos Paz, Córdoba, Argentina
Reunión:
Congreso; SAIB; 2008
Resumen:
<!-- /* Font Definitions */ @font-face {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:-1610611985 1107304683 0 0 159 0;} @font-face {font-family:Calibri; panose-1:2 15 5 2 2 2 4 3 2 4; mso-font-charset:0; mso-generic-font-family:swiss; mso-font-pitch:variable; mso-font-signature:-1610611985 1073750139 0 0 159 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-unhide:no; mso-style-qformat:yes; mso-style-parent:""; margin-top:0cm; margin-right:0cm; margin-bottom:10.0pt; margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi; mso-fareast-language:EN-US;} .MsoChpDefault {mso-style-type:export-only; mso-default-props:yes; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi; mso-fareast-language:EN-US;} .MsoPapDefault {mso-style-type:export-only; margin-bottom:10.0pt; line-height:115%;} @page Section1 {size:612.0pt 792.0pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:35.4pt; mso-footer-margin:35.4pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> Biofilms are multicellular aggregates of bacteria, enclosed in a self-produced polymeric matrix attached to an abiotic or biotic surface. Within the biofilm, bacteria are protected from different harmful factors. Biofilm formation involves the attachment of free-leaving bacteria facilitating the attachment of others. The biofilm grows through cell division and recruitment of new cells. In the final stages the biofilm changes and water channels appear. The shape becomes mushroom like. Xac, the etiological agent of canker disease has two operons xcs and xps encoding for different type II secretion systems (SSTII). Mutations in different genes of these operons have shown to confer phenotypic alterations in plant symptoms and to affect the initial steps of biofilm formation. The analysis of the biofilm by confocal microscopy has also shown that xcs and xps mutants are impaired in the development of mature structures. The evidences of the involvement of SSTII in the ability of bacteria to adhere to a surface and biofilm formation and the high identity of these systems with the type IV pilus indicates that xcs andms could be directly involved in the adhesion process. However, the analysis of secreted enzymes showed that the xps operon is responsible for degrading different  xps systekinds of substrates, such as starch and proteins, while the xcs operon is not.