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:22-1</font></em></font></strong></font></td></tr><tr><td colspan=2><br><br><table align=center width=700><tr><td><b>Poster (Painel)</b><br><table width="100%"><tr><td width="60">22-1</td><td><b>Proteomic analysis of Paracoccidioides brasiliensis during hypoxic condition</b></td></tr><tr><td valign=top>Authors:</td><td><u>Patrícia de Sousa Lima </u> (UFG - Universidade Federal de Goiás) ; Ana Flávia Parente (UFG - Universidade Federal de Goiás) ; Clayton Luiz Borges (UFG - Universidade Federal de Goiás) ; Alexandre Melo Bailão (UFG - Universidade Federal de Goiás) ; Célia Maria de Almeida Soares (UFG - Universidade Federal de Goiás) </td></tr></table><p align=justify><b><font size=2>Abstract</font></b><p align=justify class=tres><font size=2>Oxygen concentrations in the human tissues are reported to be drastically lower than in the atmosphere and vary significantly among anatomical sites. While hypoxic adaptation mechanisms have been explored in non-pathogenic microbes and mammalian/human cells, little information exists on the influence of hypoxia on microbial pathogens. A novel oxygen sensing pathway has been identified in the fission yeast <i>Schizosaccharomyces pombe</i> that responds to environmental oxygen concentrations by sensing changes in sterol levels in cell membranes. Sterol biosynthetic pathways are conserved in eukaryotes and it is dependent of oxygen since the enzymes require this molecule for activity. In mammalian and in <i>Cryptococcus neoformans</i>, cobalt chloride (CoCl2) has been used as a chemical agent that reportedly induces a biochemical and molecular response similar to that observed under low-oxygen conditions. Thus, the aim of this study was identify proteins that are differentially expressed in <i>Paracoccidioides brasiliensis</i> under hypoxic conditions using CoCl2. <i>P. brasiliensis</i> is the causal agent of paracoccidioidomycosis, which is the most prevalent systemic mycoses in Latin America. The yeast cells were treated with CoCl2 and initially, the quantitative RT-PCR analysis of genes involved in global response to hypoxia suggested response of <i>P. brasiliensis</i> to this condition. Thereby, the cells were collected after 12 h of treatment and the proteins were analyzed by 2D electrophoresis. Protein spots were selected based on staining intensity of the Coomassie blue stained gels. Statistical analysis demonstrated 156 differentially expressed proteins. The proteins were excised and digested with trypsin. Accurate peptides masses were determined by MALDI-Q-TOF MS/MS (Synapt,Waters) and protein identification was performed using Mascot software. Interestingly, the identified preliminary proteins were involved in glycolysis, fatty acid metabolism, tricarboxylic acid cycle, cell redox homeostasis, amino acid metabolism, and ubiquitin-dependent protein catabolic process. These results suggest that <i>P. brasiliensis</i> shift its metabolism to anaerobic condition under oxygen limit in an attempt to adapt to the hypoxic condition. This work can contribute to elucidate the impact of hypoxia on infection, virulence and pathogenesis of <i>P. brasiliensis</i>.</font></p><br><b>Keyword: </b>&nbsp;Paracoccidioides brasiliensis, CoCl2, hypoxia</td></tr></table></tr></td></table></body></html>