Identification of pathogenic nonsporulating molds in eyes by internal transcribed spacer sequences alignment

Abstract

AIM: To identify the species and genus of pathogenic nonsporulating molds(NSM)by internal transcribed spacer(ITS)sequences alignment, and reveal the biodiversity of NSM in Hainan Island with tropical climate. METHODS: Nine teen fungal strains, identified as NSM by conventional method in the laboratory department of Hainan Province Eye Hospital, were involved in this study. All of the strains were isolated from the infectious eye tissues from patients, and cultured with potato-dextrose agar and Sabourand's agar in 37℃ incubator for 7-21d. Any reproductive structure was detected by microscopy for up to 21d. After growth for 3-7d, the genomic DNA of specimens were extracted by grinding method combined with chemical method. Then, ITS sequences in the ribosome were amplified by PCR and analyzed using the National Center for Biological Information(NCBI)GenBank database. Finally, the species and genus were confirmed by sequence alignment. RESULTS: The corresponding target bars could be observed in all 19 specimens after PCR. The results from genetic alignment classified the 19 specimens into 12 species, including Lasiodiplodia theobromae(6 isolates), Curvalaria lunata(1 isolate), Arthrinium sp.(2 isolates), neodeightonia subglabosa(2 isolates), Earliella scabrosa(1 isolate), Hypocreales sp.(1 isolate), phoma multirostrata(1 isolate), Trichophyton rubrum(1 isolate), Aspergillus westerdijkiae(1 isolate), roussoella siamensis(1 isolate), Ceriporia lacerata(1 isolate), Fusarium solqni(1 isolate).CONCLUSION: ITS sequence alignment can identify NSM to genus and species level. The NSM in Hainan Island contains varies species, and is associated with multiple infectious diseases of the eye.

Keywords

• nonsporulating molds
• etiology
• internal transcribed spacer sequence alignment
• internal transcribed spacer sequence alignment