Invasive <em>Aspergillus terreus</em> morphological transitions and immunoadaptations mediating antifungal resistance

Abstract

Background and aimsAspergillus terreus Thom is a pathogen of public health and agricultural importance for its seamless abilities to expand its ecological niche. The aim of this study was holistically to investigate A. terreus morphological and immunoadaptations and their implication in antifungal resistance and proliferation during infection.Materials and methodsIn-depth unstructured mining of relevant peer-reviewed literature was performed for A. terreus morphological, immune, resistance, and genetic diversity based on the sequenced calmodulin-like gene.ResultsAccessory conidia and phialidic conidia produced by A. terreus confer discrete anti-fungal resistance that ensures survivability during therapies. Interestingly, by producing unique metabolites such as Asp–melanin and terretonin, A. terreus is capable of hijacking macrophages and scavenging iron, respectively. As such, A. terreus has established a rare mechanism to mitigate phagocytosis and swing the interaction dynamics in favor of its proliferation and survival in hosts.ConclusionIt is further unraveled that besides A. terreus genetic diversity, morphological, biochemical, and immunologic adaptations associated with conidia germination and discharge of chemical signals during infection enable masking of the host defense as an integral part of its strategy to survive and rapidly colonize hosts.

Complete genome sequence of lovastatin producer Aspergillus terreus ATCC 20542 and evaluation of genomic diversity among A. terreus strains

“…The predicted absence of the core genes from the terretonin and (+)-geodin pathway in A. terreus ATCC 20542 and both, A. terreus IFO 6365 and TN-484, respectively, may be important in the context of invasive fungal infections, since these metabolites have been identified as pathogenicity factors in A. terreus (reviewed in Bengyella et al 2017 and Shankar et al 2018 ). It is possible that the absence of these genes as well as those of other predicted SM gene clusters may influence pathogenic potential of these strains.…”

Lipid-Like Biofilm from a Clinical Brain Isolate of Aspergillus terreus: Quantification, Structural Characterization and Stages of the Formation Cycle

“…Filamentous fungi of the genus Aspergillus are described as saprobes or opportunistic pathogens, and these behaviors are conditioned by multifactorial interactions such as host type, host immune status, fungal inoculum concentration, conidial diameter, climatic conditions, and the expression of virulence factors of each Aspergillus species [1,13,30]. Speci cally for A. terreus, some virulence factors have been described [2,[30][31][32][33][34][35]. Additionally, A. terreus is related to its ability to develop a bio lm [30,36], although it has not been described in detail at the quantitative and structural level.…”

“…In A. terreus, other modi ed asexual structures (phialidic and globular accessory conidia) have been reported, attributing to them an invasion effect on the infected host, in combination with other fungal virulence factors. Future studies should focus on de ning their role in the metabolism of the fungus [33].…”

Exploring the extremes: applying high concentration of yeast extract leads to drastic morphological changes and elimination of (+)-geodin and asterric acid production in Aspergillus terreus submerged cultures

“…Moreover, the distribution of accessory conidia on the colonizing hyphae was demonstrated to follow two distinct patterns (i.e. thorn-like or opposing) (see Bengyella et al ( 2017 ) and references therein). The remarkable morphological adaptability displayed by this species is believed to be important in terms of invading the host (Vyas 2011 ).…”