ÿþ<HTML><HEAD><TITLE>XI International Meeting on Paracoccidioidomycosis</TITLE><link rel=STYLESHEET type=text/css href=css.css></HEAD><BODY aLink=#ff0000 bgColor=#FFFFFF leftMargin=0 link=#000000 text=#000000 topMargin=0 vLink=#000000 marginheight=0 marginwidth=0><table align=center width=700 cellpadding=0 cellspacing=0><tr><td align=left bgcolor=#cccccc valign=top width=550><font face=arial size=2><strong><font face=Verdana, Arial, Helvetica, sans-serif size=3><font size=1>XI International Meeting on Paracoccidioidomycosis</font></font></strong><font face=Verdana size=1><b><br></b></font><font face=Verdana, Arial,Helvetica, sans-serif size=1><strong> </strong></font></font></td><td align=right bgcolor=#cccccc valign=top width=150><font face=arial size=2><strong><font face=Verdana, Arial, Helvetica, sans-serif size=1><font size=1>Resume:112-3</font></em></font></strong></font></td></tr><tr><td colspan=2><br><br><table align=center width=700><tr><td><b>Oral / Poster</b><br><table width="100%"><tr><td width="60">112-3</td><td><b>Paracoccidioides brasiliensis: proteomic analysis and possible correlation with virulence</b></td></tr><tr><td valign=top>Authors:</td><td>Cristiane Candida do Amaral (UNIFESP - Federal University of São Paulo) ; Geisa Ferreira Fernandes (UNIFESP - Federal University of São Paulo) ; <u>Anderson Messias Rodrigues </u> (UNIFESP - Federal University of São Paulo) ; Priscila Oliveira dos Santos (UNIFESP - Federal University of São Paulo) ; Zoilo Pires de Camargo (UNIFESP - Federal University of São Paulo) </td></tr></table><p align=justify><b><font size=2>Abstract</font></b><p align=justify class=tres><font size=2><i>Paracoccidioides brasiliensis</i> is the agent of paracoccidioidomycosis, common in many countries of Latin America. The diversity of clinical forms of the disease has been attributed to host-related factors, mainly to the impairment of the immune system; this can also be attributed to the fungus, since differences in physiological and biochemical characteristics among various <i>P. brasiliensis</i> isolates have been demonstrated. Thus, the understanding of the molecules mediating interactions at the host-fungal interface and identification of key virulence factors may help to understand the disease. The aim of this study was to verify differentially expressed protein profiles among <i>P. brasiliensis</i> strains isolated from nature by two-dimensional gel electrophoresis (2-DE) and to compare with the degree of pathogenicity in murine model. Our results showed that isolates presented three degrees of virulence: high (Bot 1-96, Ibiá T1, Ibiá, Pb18), intermediate (T2) and low virulence (262 Uber, T1, Ibiá T2, Pinguim) and no correlation between natural source or geographic origin and virulence was found. A comparative analysis of proteomic maps from <i>P. brasiliensis</i> isolates was performed and several proteins associated with the pathogenesis of <i>P. brasiliensis</i> were identified by LC-MS/MS. When we compared the protein profiles of high virulent with those presenting intermediate virulence in terms of differentially expressed proteins we observed that 16 spots were exclusively over-expressed in isolates exhibiting high virulence phenotype: proteins associate with host parasite interaction (fructose-bisphosphate aldolase), adherence (glyceraldehyde-3-phosphate dehydrogenase), oxidative mechanisms (catalase) and environmental stress (Hsp70). In contrast, when we compared the high virulent isolates with the low virulence group, we observed that 4 proteins were over-expressed: acid nucleic synthesis (nucleic acid-binding protein) and ribosomal proteins (40S ribosomal protein S7). Our findings demonstrated that expression of specific proteins by high and low virulence parasites could be associated with the ability to interact with the host. Such data represent important step towards understanding of the complex interaction network of proteins that participate in the mechanism of pathogenesis <i>P. brasiliensis</i>. This study was supported by FAPESP, CNPq, and CAPES</font></p><br><b>Keyword: </b>&nbsp;Paracoccidioides brasiliensis, Proteomic, Virulence, Protein expression, Two dimensional gel electrophoresis</td></tr></table></tr></td></table></body></html>