Diversity in Paracoccidioides brasiliensis. the PbGP43 gene as a genetic marker

Paracoccidioides brasiliensis is a temperature-dependent dimorphic fungus and the agent of paracoccidioidomycosis (PCM), which is prevalent in rural workers of Latin American countries. Until a decade ago, most of the studies involving P. brasiliensis used clinical isolates, since environmental samples from soil are difficult to obtain. More recently, P. brasiliensis has been isolated from infected wild and domestic animals, especially from the nine-banded armadillo Dasypus novemcinctus in Brazil. Over the years, diversity within the species has been observed at several phenotypic levels. the present review will discuss the reports focusing on genetic polymorphism, which culminated with the detection of P. brasiliensis phylogenetic species as a result of a multilocus study. Polymorphism in the PbGP43 gene is detailed. This gene encodes fungal glycoprotein gp43, a dominant P. brasiliensis antigen largely studied in the last two decades for its importance in diagnosis, immune protection, and adhesive properties to extracellular matrix-associated proteins. Fungal traits associated with genetic groups are discussed.Universidade Federal de São Paulo, Div Cell Biol, BR-04023062 São Paulo, BrazilCIB, Medellin, ColombiaUniv Antioquia, Medellin, ColombiaUniv Fed Minas Gerais, Div Microbiol, Belo Horizonte, MG, BrazilUniversidade Federal de São Paulo, Div Cell Biol, BR-04023062 São Paulo, BrazilWeb of Scienc

Identification and characterization of expressed retrotransposons in the genome of the Paracoccidioides species complex

Background: Species from the Paracoccidioides complex are thermally dimorphic fungi and the causative agents of paracoccidioidomycosis, a deep fungal infection that is the most prevalent systemic mycosis in Latin America and represents the most important cause of death in immunocompetent individuals with systemic mycosis in Brazil. We previously described the identification of eight new families of DNA transposons in Paracoccidioides genomes. in this work, we aimed to identify potentially active retrotransposons in Paracoccidioides genomes.Results: We identified five different retrotransposon families (four LTR-like and one LINE-like element) in the genomes of three Paracoccidioides isolates. Retrotransposons were present in all of the genomes analyzed. P. brasiliensis and P. lutzii species harbored the same retrotransposon lineages but differed in their copy numbers. in the Pb01, Pb03 and Pb18 genomes, the number of LTR retrotransposons was higher than the number of LINE-like elements, and the LINE-like element RtPc5 was transcribed in Paracoccidioides lutzii (Pb01) but could not be detected in P. brasiliensis (Pb03 and Pb18) by semi-quantitative RT-PCR.Conclusion: Five new potentially active retrotransposons have been identified in the genomic assemblies of the Paracoccidioides species complex using a combined computational and experimental approach. the distribution across the two known species, P. brasiliensis and P. lutzii, and phylogenetics analysis indicate that these elements could have been acquired before speciation occurred. the presence of active retrotransposons in the genome may have implications regarding the evolution and genetic diversification of the Paracoccidioides genus.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Univ Fed Minas Gerais, Inst Ciencias Biol, Dept Microbiol, BR-31270901 Belo Horizonte, MG, BrazilUniv Fed Minas Gerais, Inst Ciencias Biol, Programa Posgrad Bioinformat, BR-31270901 Belo Horizonte, MG, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Imunol & Parasitol, BR-04023062 São Paulo, SP, BrazilUniv Brasilia, Inst Ciencias Biol, Lab Biol Mol, BR-70910900 Brasilia, DF, BrazilUniv Fed Goias, Inst Ciencias Biol, Lab Biol Mol, BR-74001970 Goiania, Go, BrazilFIOCRUZ Minas, Ctr Pesquisas Rene Rachou, Grp Informat Biossistemas, BR-30190002 Belo Horizonte, MG, BrazilUniv Fed Minas Gerais, Dept Biol Geral, BR-31270901 Belo Horizonte, MG, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Imunol & Parasitol, BR-04023062 São Paulo, SP, BrazilFAPEMIG: APQ-01661-13CNPq: 301652/2012-0CNPq: 486618/2013-7Web of Scienc

Synthetic Peptides Mimic gp75 from Paracoccidioides brasiliensis in the Diagnosis of Paracoccidioidomycosis

Paracoccidioidomycosis (PCM) is a systemic granulomatous disease, endemic in Latin America, caused by the thermal dimorphic fungus Paracoccidioides brasiliensis. Although some fungal antigens have already been characterized and used for serological diagnosis, cross-reactions have been frequently observed. Thus, the examination of fungal forms in clinical specimens or isolation of P. brasiliensis by culture is still the most frequent method for the diagnosis of this mycosis. In this study, a random peptide phage display library was used to select mimotopes of P. brasiliensis, which were employed as antigens in an indirect enzyme-linked immunosorbent assay. The protective monoclonal antibody against experimental PCM (anti-gp75) was used as molecular target to screen a phage display library. That approach led to a synthetic peptide named P2, which was synthesized and tested against PCM patients’ sera to check whether it was recognized. There was significant recognition of P2 by sera of untreated PCM patients when compared with normal human sera. Sera from treated PCM group, patients with other mycosis or co-infected with HIV had much lower recognition of P2 than untreated patient group. The test showed a sensitivity of 100 and 94.59% of specificity in relation to human sera control. These data indicate a potential use of P2 as diagnostic tool in PCM. Its application for serological diagnosis of PCM may contribute to the development and standardization of simpler, faster and highly reproducible immunodiagnostic tests at low cost

The antimicrobial activity of lapachol and its thiosemicarbazone and semicarbazone derivatives

Lapachol was chemically modified to obtain its thiosemicarbazone and semicarbazone derivatives. These compounds were tested for antimicrobial activity against several bacteria and fungi by the broth microdilution method. The thiosemicarbazone and semicarbazone derivatives of lapachol exhibited antimicrobial activity against the bacteria Enterococcus faecalis and Staphylococcus aureus with minimal inhibitory concentrations (MICs) of 0.05 and 0.10 µmol/mL, respectively. The thiosemicarbazone and semicarbazone derivatives were also active against the pathogenic yeast Cryptococcus gattii (MICs of 0.10 and 0.20 µmol/mL, respectively). In addition, the lapachol thiosemicarbazone derivative was active against 11 clinical isolates of Paracoccidioides brasiliensis, with MICs ranging from 0.01-0.10 µmol/mL. The lapachol-derived thiosemicarbazone was not cytotoxic to normal cells at the concentrations that were active against fungi and bacteria. We synthesised, for the first time, thiosemicarbazone and semicarbazone derivatives of lapachol. The MICs for the lapachol-derived thiosemicarbazone against S. aureus, E. faecalis, C. gattii and several isolates of P. brasiliensis indicated that this compound has the potential to be developed into novel drugs to treat infections caused these microbes