Multiple-strainTrichophyton mentagrophytesinfection in a silver fox (Vulpes vulpes) from a breeding farm

Abstract

Dermatophyte infections are extremely frequent worldwide, and their epidemiological features and distribution make them one of the most frequent infections all over the world. We identified and analysed multiform T. mentagrophytes strains isolated from a silver fox (Vulpes vulpes) kept on a breeding farm. Identification of dermatophyte strains was carried out traditionally by correlating both the clinical manifestations of the infection with a micro- and macroscopic examination. To confirm the species affiliation fully, molecular differentiation methods were used. DNA was isolated from the dermatophytes with the phenol-chloroform method. The reaction of chitin synthase 1 (chs1) amplification was carried out to confirm the dermatophytes. The phylogenetic analysis was based on the ITS sequences. The polymerase chain reaction melting profile (PCR-MP) procedure was used for differentiation of dermatophyte genomes. Direct analysis of the material sampled from the clinical lesions revealed the presence of arthrospores in the samples collected from all animals with skin lesions. The macromorphology of the colonies obtained from material sampled from the same individual was not homogeneous. The PCR-MP electrophoregram indicated high variability of their genomes. Although the dermatophytes were isolated from one infected fox, no two identical genomic profiles were obtained. The PCR-MP result corresponds with the phenotypic diversity of the isolates. The findings about the multiple dermatophyte infection in one individual complicate any future epidemiology work and other clinical investigation. Previously, using only morphological characteristics, it had been assumed that one fungal isolate per patient could be diagnosed. The novel findings encourage application of the newly developed molecular typing methods in the diagnosis of dermatophytosis.

In search of the source of dermatophytosis: Epidemiological analysis of Trichophyton verrucosum infection in llamas and the breeder (case report)

“…The pathogenic potential of a dermatophyte depends on its ability to produce various enzymes. In turn, variations in the enzymatic profile and its potential might be responsible for differences in the pathogenic effects in different hosts (Dalis et al, 2014;Gnat et al, 2019;Sharma, Hoog, Presber, & Gräser, 2007;Vermout et al, 2008). In this context, interesting data are provided by studies of the enzymatic activity of the same strain in different hosts and different types of infection.…”

The host range of dermatophytes, it is at all possible? Phenotypic evaluation of the keratinolytic activity of Trichophyton verrucosum clinical isolates

“…Keratin renders animals more robust against both abiotic stress and, which is its most important function, microbial attack . Although only a few species of prokaryotic organisms, that is, Bacillus licheniformis or Bacillus subtilis, are equipped with enzymes with keratin degradation activity, these enzymes commonly occur in dermatophytes, that is, Trichophyton verrucosum, Trichophyton mentagrophytes, Trichophyton equinum, Trichophyton gallinae, Microsporum canis and many more, but rarely in other eukaryotic microorganisms, that is, Aspergillus niger, Aspergillus flavus, Penicillium purpurogenum or Fusarium solani . Thus, microbial degradation of keratin is not widespread in nature outside the dermatophyte group, and keratin can serve as an efficient defence even against microbial attack …”

“…In conclusion, our studies indicate high keratinolytic activity of T. verrucosum clinical isolates, although contrary to expectations, it was not statistically significantly higher than in the case of the reference strain. The production of keratin-degrading enzymes seems to be a function of time, 2,4,10,27,58,66 with the peak of its activity occurring in the second week after inoculation. 64 In turn, the range of infected hosts for T. verrucosum strains has been estimated as wide, which is consistent with the literature data, 25,26,68 although the effect of keratinases is significantly higher for keratin from Cows and sheep than from other species of animals and Humans.…”

“…Remarkably, enzymes secreted by dermatophytes can underlie fungal survival on the host and development of infection, not only by providing nutrients due to the detriment of the keratinised barrier, but also by triggering and modulating the immune response . Our knowledge about the range of potentially pathogenically useful enzymes produced by dermatophytes is constantly growing, and several of them with well‐known properties have been characterised at the molecular level . Indeed, a biological characteristic of dermatophytes is their main ability to invade keratinised tissues by producing keratinases as key enzymes in pathogenesis …”

“…10,[13][14][15] Our knowledge about the range of potentially pathogenically useful enzymes produced by dermatophytes is constantly growing, and several of them with well-known properties have been characterised at the molecular level. 3,4,[16][17][18][19] Indeed, a biological characteristic of dermatophytes is their main ability to invade keratinised tissues by producing keratinases as key enzymes in pathogenesis. 10,15,20 Keratin-the main component of the surface layers of epidermis constituting 95% of stratum corneum-is a protein with a high number of disulphide bonds, water insolubility and high resistance to proteolytic enzymes.…”