Virulence of Paracoccidioides brasiliensis isolates can be correlated to groups defined by random amplified polymorphic DNA analysis

Abstract

Fifteen Paracoccidioides brasiliensis isolates were discriminated by the RAPD analysis into two groups with only 17% of genomic identity. The ability of P. brasiliensis isolates to invade tissues was studied in an experimental model using susceptible B10.A mice. The analysis was performed according to the severity of the lesions including the number and size of the granuloma, the number and dissemination of fungi to different organs. The isolates from two RAPD groups demonstrated a marked difference in their virulence patterns for B10.A mice. The isolates Pb S, 662, Bt and 166 (group I) elicited localized infection restricted to the liver showing compact epithelioid granuloma with few fungi in the early post-infection period (slightly virulent). On the other hand the isolates Pb 01 and 7455 (group II) elicited a disseminated infection with a mixed suppurative and looser granulomatous inflammation, showing extensive areas of necrosis and large numbers of viable fungal cells (highly virulent). These results are strong evidence for correlation between RAPD patterns and the virulence degree of P. brasiliensis.

Paracoccidioides brasiliensis: chemical and molecular tools for research on cell walls, antifungals, diagnosis, taxonomy

“…Previous RAPD analyses [50][51][52], RFLP [53], and partial sequences of some genes [54,55] from several P. brasiliensis isolates, revealed genetic variability and clusters correlated with geography [50,53] or virulence [51,56]. Based on phylogenetic analysis of 65 P. brasiliensis isolates, Matute et al [57] recently proposed three distinct phylogenetic species within P. brasiliensis: S1 (a paraphyletic group formed by 38 isolates of Argentinean, Brazilian, Peruvian and Venezuelan origins, plus an isolate from an Antarctic penguin), PS2 (six isolates, five of them of Brazilian origin, and one Venezuelan) and PS3 (21 Colombian isolates).…”

Identification of a gene encoding adaptin-like protein in the Paracoccidioides brasiliensis genome by random amplified polymorphic DNA analysis

“…Calcagno et al (1998) demonstrated that genetic variations could be associated with geographical regions but not with different clinical manifestations of paracoccidioidomycosis. However, Molinari-Madlum et al (1999) showed that RAPD profiles could be correlated with the degree of virulence of the P. brasiliensis isolates. Our results support the hypothesis that there is an influence of in vitro subculturing on the genotype of P. brasiliensis.…”

“…Random primers have been refined so that they can be used to distinguish and characterize genetic diversity among isolates of P. brasiliensis (Molinari-Madlum et al, 1999;Soares et al, 1995;Motta et al, 2002) and could differentiate the fungus based on virulence (Kurokawa et al, 2005).…”

Analysis of the genetic polymorphism of Paracoccidioides brasiliensis and Paracoccidioides cerebriformis "Moore" by random amplified polymorphic DNA (RAPD) and 28S ribosomal DNA sequencing: Paracoccidioides cerebriformis revisited

“…They suggested that a molecular analysis would be necessary in order to better characterize and identify this fungus 5 . Recently, several papers have shown the use of molecular biology techniques to analyze the genomic variation of fungal different taxonomical levels 1,2,7,8,10 .…”

“…It is based on the sensitive PCR technique, but with the advantage of requiring simpler procedures, due to the use of arbitrary primers and no "a priori" knowledge of target DNA sequences 8,14,16 . This technique has been useful to discriminate isolates of fungus, such as Histoplasma capsulatum and Paracoccidioides brasiliensis 1,8,10,14 . In the present investigation we used the RAPD technique to characterize the genetic affiliation between Paracoccidioides brasiliensis and Paracoccidioides cerebriformis strains.…”