Rapid and specific identification of Sporothrix schenckii by PCR targeting the DNA topoisomerase II gene

Background: In order to study the genotype variation of Sporothrix schenckii, we previously analyzed the genomic sequences of the DNA topoisomerase 11 genes of this fungus and S. schenckii-related species, such as S. schenckii var. luriei and Ceratocystis stenoceras. Objective: To develop a PCR-based identification system that can distinguish S. schenckii from its related species for clinical diagnosis of sporotrichosis. Methods: Based on the nucleotide sequences of the DNA topoisomerase II genes of S. schenckii, S. schenckii var. luriei and C. stenoceras, three gene-specific primers (SSHF31 and SSHR97 for S. schenckii, and SSLF64 for S. schenckii var. luriei) were designed and evaluated for their specificities in PCR amplifications. Results: The primer set SSHF31/SSHR97 amplified PCR products of 663-817 bp from S. schenckii and approximately 660 bp from S. schenckii var. luriei, while SSLF64/SSHR97 exclusively amplified a major product of 305 bp from S. schenckii var. luriei. Conclusion: PCR targeting the DNA topoisomerase 11 gene specifically and rapidly distinguished S. schenckii from its related species. (c) 2005 Japanese Society for Investigative Dermatology. published by Elsevier Ireland Ltd. All rights reserved.