Fonsecaea and Cladophialophora are genera of black yeast-like fungi harboring agents of a mutilating implantation disease in humans, along with strictly environmental species. The current hypothesis suggests that those species reside in somewhat adverse microhabitats, and pathogenic siblings share virulence factors enabling survival in mammal tissue after coincidental inoculation driven by pathogenic adaptation. A comparative genomic analysis of environmental and pathogenic siblings of Fonsecaea and Cladophialophora was undertaken, including de novo assembly of F. erecta from plant material. The genome size of Fonsecaea species varied between 33.39 and 35.23 Mb, and the core genomes of those species comprises almost 70% of the genes. Expansions of protein domains such as glyoxalases and peptidases suggested ability for pathogenicity in clinical agents, while the use of nitrogen and degradation of phenolic compounds was enriched in environmental species. The similarity of carbohydrate-active vs. protein-degrading enzymes associated with the occurrence of virulence factors suggested a general tolerance to extreme conditions, which might explain the opportunistic tendency of Fonsecaea sibling species. Virulence was tested in the Galleria mellonella model and immunological assays were performed in order to support this hypothesis. Larvae infected by environmental F. erecta had a lower survival. Fungal macrophage murine co-culture showed that F. erecta induced high levels of TNF-α contributing to macrophage activation that could increase the ability to control intracellular fungal growth although hyphal death were not observed, suggesting a higher level of extremotolerance of environmental species.

Aim: To evaluate and characterize the etiopathogenesis of the fusarial onychomycosis in an ex vivo study through fragments of sterile human nail, without the addition of any nutritional source. Materials & methods: The infection and invasion of Fusarium oxysporum in the nail were evaluated by scanning electron microscopy (SEM), CFU, matrix, histopathology and Fourier Transform Infrared Spectrometer coupled to an equipment with diamond accessory (FTIR-ATR). Results: F. oxysporum infected and invaded across the nail, regardless of application face. However, the dorsal nail surface was the strongest barrier, while the ventral was more vulnerable to infection and invasion process. The fungal–nail interaction resulted in the formation of a dense biofilm. Conclusion: F. oxysporum infect and invade the healthy human nail, resulting in biofilm formation. Therefore, F. oxysporum is likely a primary onychomycosis agent.

The prevalence of extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae varies worldwide, however, the incidence of ESBL-producing environmental Salmonella isolates is increasing. Salmonella is still one of the most important pathogens that occur in the poultry supply chain. Therefore, this study analyzed the susceptibility of Salmonella isolates collected from a poultry supply chain to β-lactam antibiotics, and examined the phenotypes of the isolates based on enzyme-inducible AmpC β-lactamase analysis. All analysis of the putative positive isolates in the current study confirmed that 27.02% (77/285 analysis) of all ESBL tests realized with the isolates produced a profile of resistance consistent with β-lactamase production. All isolates of S. Minnesota serotype had ESBL phenotype. Aztreonam resistance was the least common amongst the Salmonella isolates, followed by ceftazidime. The presence of inducible chromosomal ESBL was detected in 14 different isolates of the 19 serotypes investigated. These results are very indicatives of the presence of ESBL genes in Salmonella isolates from a broiler supply chain, reaffirming the growing global problem of ESBL resistance.

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