The intergenic spacer region of the ribosomal DNA gene of Histoplasma capsulatum var. capsultaum and its sequence diversity among Argentinean isolates.

LANDANBURU F; CUESTAS ML; RUBIO A; ELÍAS N; LÓPEZ DANERI G; VECINO C; IOVANNITTI C; MUJICA MT

MYCOSES

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2014

0933-7407

ITS regions of rDNA genes of 49 Histoplasma capsulatum (48 from clinical samplesand one from soil) isolates were examined. Nucleotide sequence heterogeneity withinthis region was useful for phylogenetic classification of H. capsulatum and speciesidentification. Thus, in 45 of 49 isolates we observed higher percentages of identityin the nucleotide sequences of ITS regions when the isolates studied herein werecompared with those reported in our country in the South America B clade. Phylo-genetic analyses of rDNA sequences corresponding to the 537 bp of the ITS regionobtained from H. capsulatum isolates assigned South America type B clade (45 iso-lates), North America type 1 and Asia clade (2 isolates each one). H. capsulatumstrains isolated from soil and from patients living in Argentina (45 of 49) clusteredtogether with the H. capsulatum isolates of the South America B clade. The high levelof genetic similarity among our isolates suggests that almost one genetic populationis present in the microenvironment. Isolates described as H. capsulatum var. capsulatumor var. farciminosum (2 isolates) did not form a monophyletic group and werefound in the Asia clade. Subsequent studies are needed to properly identify theseisolates.