en Anti-microbial agents, resistance and treatment protocols Anti-microbial agents, resistance and treatment protocols Original article Original article <p dir="ltr"><strong><span style="font-family:garamond,serif;"><span style="font-size:10.0pt;">Introduction:</span></span></strong><span style="font-family:garamond,serif;"><span style="font-size:10.0pt;"> <em>Aspergillus fumigatus</em> is the leading cause of invasive aspergillosis in immunocompromised patients with a high rate of mortality. Despite introduction of several classes of antifungal drugs, the limitations of current therapies have prompted an intense research toward the discovery of new antifungal compounds. In a recent study, several potential drug targets were identified based on <em>in silico</em> comparative proteome analyses of <em>A. fumigatus</em> and <em>Saccharomyces cerevisiae</em>. A potential target, capsule polysaccharide synthase1 (CPS1) homolog gene, was identified and chosen for further study. <strong>Methods</strong>: The genome sequence of CPS1 homolog in <em>A.&nbsp; fumigatus</em> (<em>AfuCPS1</em>) was retrieved from the database and analyzed. The RT-PCR analysis was carried out to show the presence of the transcripts. A gene disruption cassette was prepared and subsequently transformed into <em>A. fumigatus</em> strain AF293. An <em>AfuCPS1</em> disruptant strain was isolated and further analyzed. <strong>Results</strong>: The <em>AfuCPS1</em> gene sequence was annotated, and the signal sequence and a glycosyltransferase motif were identified. The RT-PCR analysis showed that <em>AfuCPS1 </em>is expressed throughout the life cycle of the fungus. The <em>AfuCPS1</em> mutant showed normal colony morphology. Antifungal susceptibility assay of the mutant using different classes of known antifungal drugs confirmed a similar susceptibility pattern to the wild-type strain. However, spore germination was affected, and a delay in germination was observed. <strong>Conclusion</strong>: The findings showed that the <em>AfuCPS</em>1 is not essential for the normal growth of <em>A. fumigatus</em>. More investigation is underway to elucidate the physiological role of this gene in spore germination process.</span></span></p> Aspergillus fumigatus, Cell wall, Gene, Spores, Aspergillosis 25 30 http://jommid.pasteur.ac.ir/browse.php?a_code=A-10-139-1&slc_lang=en&sid=1 Sepideh Farmand Azadeh sepide.farmand@yahoo.com No Department of Medical Biotechnology, Pasteur Institute of Iran, Tehran, Iran Najmeh Zarei shamimzarein@yahoo.com No Department of Medical Biotechnology, Pasteur Institute of Iran, Tehran, Iran Vahid Khalaj v_khalaj@yahoo.com No Department of Medical Biotechnology, Pasteur Institute of Iran, Tehran, Iran Mohammad Azizi mohazizi2003@yahoo.co.uk Yes Department of Medical Biotechnology, Pasteur Institute of Iran, Tehran, Iran