معرفي ايزوله جديدي از قارچ هاي مخمري جنس مالاسزيا Malassezia براساس آناليز توالي نوكلئوتيدهاي ناحيه 26S و ITS1 در DNA ي ريبوزومي

A New Isolate of the Genus Malassezia Based on the Sequence Analysis of 26S and ITS 1 in Ribosomal DNA

Malassez ia species considered to be the etiological agents of pitynasis versicolor and Malas sezia follicolitis in humans. Recently, on the baSIS of molecular data , four new species were added to the genus. In total, 11 species have been described and accepted so far. In this study we describe a new isolate of Malassezia based on the nucleotide sequence of 26SrDNA and ITS1 regions, as the accepted critical markers for des cription of the species . The yeast was isolated from a hamster. Two primer pairs, one for amplification of 0110226Sr DNA and another for the ITS1 region were used in PCR. The PCR products were sequenced and analyzed to compare with other similar sequen ces which are already deposited in the GenBank. The 26SrDNA PCR product was also digested with the restrict ion enzyme Cfo!. Malassezia-specific universal primer pairs successfully amplified the 26srDNA and ITS1 regions of the new isolate , providing a single PCR product of about 580 and 280 base pairs , respe ctively. After digestion of the 26s PCR product with the enzyme Cfol, a unique and different RFLP pattern was observed. Sequence analysis of D1/0226s and ITS1 regions were compared with the same regions in all already described Malassezia species , which implied a different and unique new sequences. The phylo genetic tree of both regions showed that the isolate could be a different Malassezia isolate. Regarding the new RFLP pattern of 0 110226SrDBA and the unique nucleotide sequence of both 01 /02 26SrDNAand ITS1 regions , we propose the isolate to be a new Malassezia.