Growth of Aspergillus fumigatus in Biofilms in Comparison to Candida albicans

Abstract

Biofilm formation during infections with the opportunistic pathogen Aspergillus fumigatus can be very problematic in clinical settings, since it provides the fungal cells with a protective environment. Resistance against drug treatments, immune recognition as well as adaptation to the host environment allows fungal survival in the host. The exact molecular mechanisms behind most processes in the formation of biofilms are unclear. In general, the formation of biofilms can be categorized roughly in a few stages; adhesion, conidial germination and development of hyphae, biofilm maturation and cell dispersion. Fungi in biofilms can adapt to the in-host environment. These adaptations can occur on a level of phenotypic plasticity via gene regulation. However, also more substantial genetic changes of the genome can result in increased resistance and adaptation in the host, enhancing the survival chances of fungi in biofilms. Most research has focused on the development of biofilms. However, to tackle developing microbial resistance and adaptation in biofilms, more insight in mechanisms behind genetic adaptations is required to predict which defense mechanisms can be expected. This can be helpful in the development of novel and more targeted antifungal treatments to combat fungal infections.

Effect of Shock Waves on the Growth of <em>Aspergillus niger</em> Conidia: Evaluation of Germination and Preliminary Study on Gene Expression

“…This may be associated with the presence of a complex protective covering, composed of a polymeric matrix of glucans and chitin, with arrangements of melanin and hydrophobic proteins on the external layer. According to Valsecchi et al [62], artificially removing the melanin and hydrophobins does not affect germination, since disaggregation of this layer occurs naturally during the swelling phase [48,62]. Our study shows that the conidia were activated and began the process of isotropic growth (swelling) until they reached twice their initial cellular area after treatment with shock waves generated at 4 kV.…”

“…The cell wall of filamentous fungi is an essential component for morphogenesis and cell viability as well as protection against external ambient stress factors [45][46][47]. Its structure is a physically rigid layer formed mainly of networks of carbohydrates (β-1,3 glucan, β-1,6 glucan, chitin), proteins (mannoproteins, hydrophobins), and other surface components, such as melanins [7,48].…”

Oxidized chondroitin sulfate eye drops ameliorate the prognosis of fungal keratitis with anti-inflammatory and antifungal effects

“…Conidia adhesion is the first step for fungal biofilm formation. 62 The number of adherent A. fumigatus conidia to the HCEC surface in the OCS-treated group (Fig. 4K–M) versus the control group (Fig.…”

Identification of viral dose and administration time in simulated phage therapy occurrences

“…albicans was modeled as that of a bacterium [18], an assumption that might not fit the actual growth of this protist [29]. Since, as the present study highlighted, phage therapy needs to be tailored for each microbial interaction, there is a demand to increase the availability of the pool of life-history traits available to microbiologists, a goal that only a multi-center effort could achieve.…”

“…For instance, since the only value available for S. mutans phage M102AD was δ, the modeling of case 4 had to be built on phage λ , which does not infect this bacterium. In addition, the growth of C. albicans was modeled as that of a bacterium [18], an assumption that might not fit the actual growth of this protist [29]. Since, as the present study highlighted, phage therapy needs to be tailored for each microbial interaction, there is a demand to increase the availability of the pool of life-history traits available to microbiologists, a goal that only a multi-center effort could achieve.…”