7 research outputs found
Biological activity of the mite Sancassania sp. (Acari: Acaridae) from bat guano associated with the pathogenic fungus Histoplasma capsulatum
Mites and the mammal pathogenic fungus Histoplasma capsulatum are the major components of bat guano microbiota. Interactions between mites and H. capsulatum were evaluated under laboratory conditions. Acarid mites, mainly Sancassania sp., were the most abundant microarthropod in the sampled guano of the Mexican bat Tadarida brasiliensis mexicana and, based on its morphology, Sancassania sp. was similar to the cosmopolitan species Sancassania sphaerogaster. The mycophagous and vectoring activities of this mite were tested for H. capsulatum and two other fungal species, Sporothrix schenckii (pathogenic) and Aspergillus sclerotiorum (non-pathogenic). S. ca. sphaerogaster was able to reproduce in H. capsulatum and S. schenckii colonies, multiplying in great numbers under controlled fungal mycelial-phase culture conditions. H. capsulatum colonies were completely destroyed after 14 days of in vitro interaction with mites. In contrast, S. ca. sphaerogaster did not reproduce in A. sclerotiorum cultures. S. ca. sphaerogaster was found vectoring H. capsulatum, but not the two other fungal species studied
Biological activity of the mite Sancassania (Acari: Acaridae) from bat guano associated with the pathogenic fungus Histoplasma capsulatum
Mites and the mammal pathogenic fungus Histoplasma capsulatum are the
major components of bat guano microbiota. Interactions between mites
and H. capsulatum were evaluated under laboratory conditions. Acarid
mites, mainly Sancassania , were the most abundant microarthropod in
the sampled guano of the Mexican bat Tadarida brasiliensis mexicana
and, based on its morphology, Sancassania sp. was similar to the
cosmopolitan species Sancassania sphaerogaster . The mycophagous and
vectoring activities of this mite were tested for H. capsulatum and two
other fungal species, Sporothrix schenckii (pathogenic) and
Aspergillus sclerotiorum (non-pathogenic). S. ca. sphaerogaster was
able to reproduce in H. capsulatum and S. schenckii colonies,
multiplying in great numbers under controlled fungal mycelial-phase
culture conditions. H. capsulatum colonies were completely destroyed
after 14 days of in vitro interaction with mites. In contrast, S. ca.
sphaerogaster did not reproduce in A. sclerotiorum cultures. S. ca.
sphaerogaster was found vectoring H. capsulatum, but not the two other
fungal species studied
Histoplasma capsulatum Isolated from Tadarida brasiliensis Bats Captured in Mexico Form a Sister Group to North American Class 2 Clade.
Histoplasma capsulatum is a dimorphic fungus associated with respiratory and systemic infections in mammalian hosts that have inhaled infective mycelial propagules. A phylogenetic reconstruction of this pathogen, using partial sequences of arf, H-anti, ole1, and tub1 protein-coding genes, proposed that H. capsulatum has at least 11 phylogenetic species, highlighting a clade (BAC1) comprising three H. capsulatum isolates from infected bats captured in Mexico. Here, relationships for each individual locus and the concatenated coding regions of these genes were inferred using parsimony, maximum likelihood, and Bayesian inference methods. Coalescent-based analyses, a concatenated sequence-types (CSTs) network, and nucleotide diversities were also evaluated. The results suggest that six H. capsulatum isolates from the migratory bat Tadarida brasiliensis together with one isolate from a Mormoops megalophylla bat support a NAm 3 clade, replacing the formerly reported BAC1 clade. In addition, three H. capsulatum isolates from T. brasiliensis were classified as lineages. The concatenated sequence analyses and the CSTs network validate these findings, suggesting that NAm 3 is related to the North American class 2 clade and that both clades could share a recent common ancestor. Our results provide original information on the geographic distribution, genetic diversity, and host specificity of H. capsulatum
Genetic diversity of Histoplasma capsulatum isolated from infected bats randomly captured in Mexico, Brazil, and Argentina, using the polymorphism of (GA)(n) microsatellite and its flanking regions
Fil: Taylor, María Lucía. Universidad Nacional Autónoma de México. Facultad de Medicina. Departamento de Microbiología-Parasitología; México.Fil: Hernández-García, Lorena. Universidad Nacional Autónoma de México. Facultad de Medicina. Departamento de Microbiología-Parasitología; México.Fil: Estrada-Bárcenas, Daniel. Universidad Nacional Autónoma de México. Facultad de Medicina. Departamento de Microbiología-Parasitología; México.Fil: Salas-Lizana, Rodolfo. Universidad Nacional Autónoma de México. Instituto de Ecología. Departamento de Ecología Evolutiva; México.Fil: Zancopé-Oliveira, Rosely M. Fundação Oswaldo Cruz. Instituto de Pesquisa Clínica Evandro Chagas. Serviço de Micología-Setor de Imunodiagnóstico; Brasil.Fil: García de la Cruz, Saúl. Universidad Nacional Autónoma de México. Facultad de Medicina. Departamento de Microbiología-Parasitología; México.Fil: Galvão-Dias, Maria A. Centro de Controle de Zoonoses de Sao Paulo; Brasil.Fil: Curiel-Quesada, Everardo. Instituto Politécnico Nacional. Departamento de Bioquímica. Escuela Nacional de Ciencias Biológicas; México.Fil: Canteros, Cristina E. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Bioquímica; Argentina.Fil: Bojórquez-Torres, Georgina. Universidad Nacional Autónoma de México. Facultad de Medicina. Departamento de Microbiología-Parasitología; México.Fil: Bogard-Fuentes, Carlos A. Universidad Nacional Autónoma de México. Facultad de Medicina. Departamento de Microbiología-Parasitología; México.Fil: Zamora-Tehozol, Erick. Universidad Nacional Autónoma de México. Facultad de Medicina. Departamento de Microbiología-Parasitología; México.The genetic diversity of 47 Histoplasma capsulatum isolates from infected bats captured in Mexico, Brazil, and Argentina was studied, using sequence polymorphism of a 240-nucleotides (nt) fragment, which includes the (GA)(n) length microsatellite and its flanking regions within the HSP60 gene. Three human clinical strains were used as geographic references. Based on phylogenetic analyses of 240-nt fragments achieved, the relationships among H. capsulatum isolates were resolved using neighbour-joining and maximum parsimony methods. The tree topologies obtained by both methods were identical and highlighted two major clusters of isolates. Cluster I had three sub-clusters (Ia, Ib, and Ic), all of which contained Mexican H. capsulatum samples, while cluster II consisted of samples from Brazil and Argentina. Sub-cluster Ia included only fungal isolates from the migratory bat Tadarida brasiliensis. An average DNA mutation rate of 2.39 × 10(-9) substitutions per site per year was estimated for the 240-nt fragment for all H. capsulatum isolates. Nucleotide diversity analysis of the (GA)(n) and flanking regions from fungal isolates of each cluster and sub-cluster underscored the high similarity of cluster II (Brazil and Argentina), sub-clusters Ib, and Ic (Mexico). According to the genetic distances among isolates, a network of the 240-nt fragment was graphically represented by (GA)(n) length haplotype. This network showed an association between genetic variation and both the geographic distribution and the ecotype dispersion of H. capsulatum, which are related to the migratory behaviour of the infected bats studied
Frequency and genetic diversity of the MAT1 locus of Histoplasma capsulatum isolates in Mexico and Brazil
The MAT1-1 and MAT1-2 idiomorphs associated with the MAT1 locus of Histoplasma capsulatum were identified by PCR. A total of 28 fungal isolates, 6 isolates from human clinical samples and 22 isolates from environmental (infected bat and contaminated soil) samples, were studied. Among the 14 isolates from Mexico, 71.4% (95% confidence interval [95% CI], 48.3% to 94.5%) were of the MAT1-2 genotype, whereas 100% of the isolates from Brazil were of the MAT1-1 genotype. Each MAT1 idiomorphic region was sequenced and aligned, using the sequences of the G-217B (+mating type) and G-186AR (-mating type) strains as references. BLASTn analyses of the MAT1-1 and MAT1-2 sequences studied correlated with their respective+ and-mating type genotypes. Trees were generated by the maximum likelihood (ML) method to search for similarity among isolates of each MAT1 idiomorph. All MAT1-1 isolates originated from Brazilian bats formed a well-defined group; three isolates from Mexico, the G-217B strain, and a subgroup encompassing all soil-derived isolates and two clinical isolates from Brazil formed a second group; last, one isolate (EH-696P) from a migratory bat captured in Mexico formed a third group of the MAT1-1 genotype. The MAT1-2 idiomorph formed two groups, one of which included two H. capsulatum isolates from infected bats that were closely related to the G-186AR strain. The other group was formed by two human isolates and six isolates from infected bats. Concatenated ML trees, with internal transcribed spacer 1 (ITS1) -5.8S-ITS2 and MAT1-1 or MAT1-2 sequences, support the relatedness of MAT1-1 or MAT1-2 isolates. H. capsulatum mating types were associated with the geographical origin of the isolates, and all isolates from Brazil correlated with their environmental sources. © 2013, American Society for Microbiology. All Rights Reserved