New Insight into Molecular Phylogeny and Epidemiology of Sporothrix schenckii Species Complex Based on Calmodulin-Encoding Gene Analysis of Italian Isolates

View at Publisher| Export | Download | Add to List | More... Mycopathologia Volume 172, Issue 3, September 2011, Pages 179-186 New Insight into Molecular Phylogeny and Epidemiology of Sporothrix schenckii Species Complex Based on Calmodulin-Encoding Gene Analysis of Italian Isolates (Article) Romeo, O., Scordino, F., Criseo, G. Department of Life Sciences Marcello Malpighi, Section of Microbiological, Genetic and Molecular Sciences, University of Messina, Viale Ferdinando Stagno d'Alcontres, 31, 98166 Messina, Italy Abstract In this study, we investigated phylogenetic relationships among Italian Sporothrix schenckii isolates, by comparing their partial calmodulin sequences. In this analysis, we used 26 environmental strains of S. schenckii, plus two autochthonous clinical isolates. The results showed that our clinical strains grouped with S. schenckii sensu stricto isolates, whereas all 26 environmental isolates co-clustered with Sporothrix albicans (now regarded as a synonym of Sporothrix pallida), a non-pathogenic species closely related to S. schenckii. Furthermore, the group of environmental strains was found to be quite heterogeneous and further subdivided into two subgroups. The data reported here also showed that molecular methods, for specific identification of S. schenckii, developed before the description of its closely related species should be used with caution because of the possibility of false positive results, which could lead to inappropriate antifungal therapy. This study improves our understanding of the distribution of these new closely related Sporothrix species which also showed significant differences in antifungal susceptibilities.