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Bromley, M. J.

Publications and source records attributed to Bromley, M. J..

15 recordsLinked to original sources
bioRxiv2026

Live 4D monitoring of fungal infection in an ex vivo model of fungal keratitis reveals enhanced efficacy of combined PACK-CXL and natamycin treatment

Fungal keratitis (FK) is a major cause of visual impairment worldwide, yet the development and evaluation of new therapeutic approaches are limited by experimental models that inadequately reproduce deep stromal infection or permit longitudinal quantification of fungal burden. Here, we developed an ex vivo porcine corneal model of Aspergillus fumigatus keratitis that supports reproducible fungal invasion into the deeper corneal stroma and enables non-destructive monitoring of infection over time. Optimisation of the culture conditions demonstrated that reducing nutrient availability markedly promoted stromal penetration compared with nutrient rich conditions. Using a YFP expressing A. fumigatus strain combined with confocal microscopy and three-dimensional image analysis, fungal burden could be quantified repeatedly within individual corneas, allowing changes in established infection to be monitored longitudinally. We applied the model to evaluate natamycin and photoactivated chromophore for keratitis corneal cross-linking (PACK-CXL), alone and in combination. Both monotherapies significantly restricted the increase in fungal burden observed in untreated corneas, but neither consistently reduced pre-existing fungal burden. In contrast, combined natamycin and PACK-CXL treatment reduced fungal burden in all treated corneas and was significantly more effective than either treatment alone. Together, these findings establish a quantitative ex vivo platform for investigating invasive A. fumigatus corneal infection and demonstrate its ability to distinguish between treatments that restrict fungal expansion and those that reduce established fungal burden. The model provides a useful approach for the longitudinal evaluation and optimisation of therapeutic interventions for fungal keratitis.

microbiology↗
bioRxiv2026

The pangenome of Aspergillus fumigatus highlights the dynamics of gene gain-loss over evolutionary timescales in a human fungal pathogen

How fungal pathogens generate and maintain genetic diversity under sustained environmental drug pressure is central to understanding the emergence of antifungal resistance. In environmental moulds such as Aspergillus fumigatus, escalating exposure to agricultural fungicides that share targets with clinical azoles imposes chronic selection outside the host, yet the genomic mechanisms enabling long-term adaptation remains unclear. Here, we reconstruct the largest eukaryotic pangenome assembled to date, comprising over 1,000 A. fumigatus isolates collected across 34 countries spanning a century. Using network-based orthogroup clustering combined with ancestral state reconstruction, we show that the A. fumigatus pangenome is open and shaped by continual gene gain and loss. Pangenome-wide association analyses identify accessory genes associated with itraconazole resistance, indicating that resistance evolution occurs within broader genomic backgrounds and beyond canonical target-site mutations. We further reveal that the accessory genome is structured into distinct evolutionary cohorts, including lineage-restricted gene sets enriched for mobile genetic element- associated domains, notably Starship-linked genes. These patterns suggest that Starships contribute to clade-specific genome architecture while remaining largely constrained by phylogenetic boundaries. Time-calibrated phylogenetic modelling reveals a relatively slow rate of gene turnover--approximately two orthogroup events per century--demonstrating that large-scale genome evolution in A. fumigatus is decoupled from elevated point mutation rates and contrasts sharply with bacterial systems. Together, these findings establish a quantitative framework for fungal pangenome evolution and reveal how structured accessory genome dynamics underpin antifungal resistance and long-term adaptation in this major human pathogen. Significance StatementAntifungal resistance in Aspergillus fumigatus threatens global health, yet the genomic processes enabling long-term adaptation under environmental drug pressure remain poorly understood. Using a global, century-spanning pangenome, incorporating over 1,000 isolates, we quantify gene gain and loss dynamics in this major human pathogen. We show that the pangenome is open but evolves slowly, with only [~]2 gene turnover events per century. Accessory genes follow two distinct evolutionary modes: some are lineage-restricted, while others are broadly distributed and dynamically exchanged. Resistance is associated with lineage-specific accessory genes, highlighting a broader role of resistance formation than target-site mutations alone. These findings reveal how heterogeneous turnover dynamics shape adaptation to widespread antifungal exposure.

evolutionary biology↗
bioRxiv2023

Elevated mutation rates in the multi-azole resistant Aspergillus fumigatus cladedrives rapid evolution of antifungal resistance

The evolution of antifungal resistance is an emerging global threat. Particularly concerning is the widespread occurrence of azole resistance within Aspergillus fumigatus, a globally ubiquitous environmental mould that causes over 1 million life-threatening invasive infections in humans each year. It is increasingly evident that the environmental use of azoles has led to selective sweeps across multiple genomic loci resulting in the rapid expansion of a genetically distinct cluster of genotypes (clade A) that results in resistance to clinically deployed azoles. Isolates within this cluster are more likely to be cross resistant to agricultural antifungals with unrelated modes of action suggesting they may be adapting rapidly to antifungal challenge. Here we show that this cluster is not only multi-azole resistant but has increased propensity to develop resistance to new antifungals because of variants in the DNA mismatch repair system. A variant in msh6 is found almost exclusively within clade A, occurs in 88% of multi-azole resistant isolates harbouring the canonical cyp51A azole resistance allelic variant TR34/L98H, and is globally distributed. Naturally occurring isolates with this msh6 variant display a 4 to 9-times higher rate of mutation, leading to an increased propensity to evolve resistance to current and next generation antifungals. We argue that pervasive environmental use of fungicides creates selective arenas whereby genotypes of A. fumigatus with increased adaptive capability thrive in the face of strong directional selection, leading to the genesis and amplification of antifungal resistance. These results help explain the pronounced clustering of multiple independent resistance mechanisms within the mutable clade A. Our findings further suggest that resistance to next generation antifungals is more likely to emerge within organisms that are already multi-azole resistant, posing a major problem due to the prospect of dual use of novel antifungals in clinical and agricultural settings.

microbiology↗
bioRxiv2023

A phylogenetic approach to explore the Aspergillus fumigatus conidial surface-associated proteome and its role in pathogenesis

Aspergillus fumigatus, an important pulmonary fungal pathogen causing several diseases collectively called aspergillosis, relies on asexual spores or conidia for initiating host infection. Here, we used a phylogenomic approach to compare proteins in the conidial surface of A. fumigatus, two closely related non-pathogenic species, Aspergillus fischeri and Aspergillus oerlinghausenensis, and the cryptic pathogen Aspergillus lentulus. After identifying 62 proteins uniquely expressed on the A. fumigatus conidial surface, we deleted 42 genes encoding conidial proteins. We found deletion of 33 of these genes altered susceptibility to macrophage killing, penetration and damage to epithelial cells, and cytokine production. Notably, a gene that encodes glycosylasparaginase, which modulates levels of the host pro-inflammatory cytokine IL-1{beta}, is important for infection in an immunocompetent murine model of fungal disease. These results suggest that A. fumigatus conidial surface proteins and effectors are important for evasion and modulation of the immune response at the onset of fungal infection.

microbiology↗
bioRxiv2023

The Cystic Fibrosis treatment, Trikafta, affects growth, viability, and cell wall of Aspergillus fumigatus biofilms

People with Cystic Fibrosis (pwCF) commonly test positive for the pathogenic fungus, Aspergillus fumigatus, which is associated with a decline in lung function. Trikafta is a recently approved therapy for pwCF that improves quantity and function of the CFTR protein, however, it is not known how Trikafta affects microbial communities in the lung. Therefore, the aim of this study was to determine whether Trikafta directly affects A. fumigatus growth and biology. While Trikafta did not impact the viability of A. fumigatus conidia, treatment of A. fumigatus biofilms with Trikafta reduced overall biofilm biomass. This finding was associated with increased membrane permeability, decreased viability, and reduced metabolic activity following long-term treatment of biofilms. Trikafta-induced membrane permeability and biomass reduction was partially blocked with the calcium channel inhibitor Verapamil and fully blocked by the mammalian CFTR inhibitor GlyH-101. Trikafta-induced biomass reduction and metabolic activity was shown to be regulated by the High Osmolarity Glycerol (HOG) pathway gene sakA. Trikafta treatment also induced resistance to the cell wall stressor calcofluor white, susceptibility to the antifungal caspofungin, and decreased inflammatory responses from murine bone marrow cells. Collectively, these results reveal that Trikafta affects infection-relevant A. fumigatus biology and host-microbial interactions. IMPORTANCEPeople with Cystic Fibrosis (pwCF) commonly test positive for the pathogenic fungus, Aspergillus fumigatus, which is associated with a decline in lung function. Trikafta is a recently approved therapy for pwCF that improves quantity and function of the CFTR protein, however, it is not known how Trikafta affects microbial communities in the CF lung. Here we report that Trikafta has anti-fungal activity against the infection relevant form of A. fumigatus, termed biofilms. When exposed to Trikafta A. fumigatus biofilms lose their viability. In addition, exposure to Trikafta enhances the susceptibility of A. fumigatus biofilms to the clinically utilized anti-fungal drug caspofungin. These data suggest Trikafta impacts the cell wall of A. fumigatus and suggests the potential for using Trikafta to augment existing anti-fungal therapy.

microbiology↗
bioRxiv2023

Mycobiome analyses of critically ill COVID-19 patients suggests antifungal prophylaxis may be protective against A. fumigatus-associated mortality

RationaleCOVID-19-associated pulmonary aspergillosis (CAPA) is a life-threatening complication in patients with severe COVID-19. Previously, acute respiratory distress syndrome in patients with COVID-19 has been associated with lung fungal dysbiosis, evidenced by reduced microbial diversity and Candida colonisation. Increased fungal burden in the lungs of critically ill COVID-19 patients is linked to prolonged mechanical ventilation and increased mortality. However, specific mycobiome signatures associated with severe COVID-19 in the context of survival and antifungal drug prophylaxis have not yet been determined and such knowledge could have an important impact on treatment. ObjectivesTo understand the composition of the respiratory mycobiome in critically ill COVID-19 patients with and without CAPA and the impact of antifungal use in patient outcome. MethodsWe performed a multi-national study of 39 COVID-19 patients in intensive care units (ICU) with and without CAPA. Respiratory mycobiome was profiled using ITS1 sequencing and Aspergillus fumigatus burden was further validated using qPCR. Fungal communities were investigated using alpha diversity, beta diversity, taxa predominance and taxa abundances. ResultsRespiratory mycobiomes of COVID-19 patients were dominated by Candida and Aspergillus. There was no significant association with corticosteroid use or CAPA diagnosis and respiratory fungal communities. Increased A. fumigatus burden was associated with mortality and, the use of azoles at ICU admission was linked with an absence of A. fumigatus. ConclusionsOur findings suggest that mould-active antifungal treatment at ICU admission may be linked with reduced A. fumigatus-associated mortality in severe COVID-19. However, further studies are warranted on this topic.

microbiology↗
bioRxiv2022

COVID-19 Associated Pulmonary Aspergillosis isolates are genomically diverse but similar to each other in their responses to infection-relevant stresses

Secondary infections caused by the pulmonary fungal pathogen Aspergillus fumigatus are a significant cause of mortality in patients with severe Coronavirus Disease 19 (COVID-19). Even though epithelial cell damage and aberrant cytokine responses have been linked with susceptibility to COVID-19 associated pulmonary aspergillosis (CAPA), little is known about the mechanisms underpinning co-pathogenicity. Here, we analysed the genomes of 11 A. fumigatus isolates from patients with CAPA in three centres from different European countries. CAPA isolates did not cluster based on geographic origin in a genome-scale phylogeny of representative A. fumigatus isolates. Phenotypically, CAPA isolates were more similar to the A. fumigatus A1160 reference strain than to the Af293 strain when grown in infection-relevant stresses; except for interactions with human immune cells wherein macrophage responses were similar to those induced by the Af293 reference strain. Collectively, our data indicates that CAPA isolates are genomically diverse but are more similar to each other in their responses to infection-relevant stresses. A larger number of isolates from CAPA patients should be studied to identify genetic drivers of co-pathogenicity in patients with COVID-19. ImportanceCoronavirus disease 2019 (COVID-19)-associated pulmonary aspergillosis (CAPA) has been globally reported as a life-threatening complication in some patients with severe COVID-19. Most of these infections are caused by the environmental mould Aspergillus fumigatus which ranks third in the fungal pathogen priority list of the WHO. However, little is known about the molecular epidemiology of Aspergillus fumigatus CAPA strains. Here, we analysed the genomes of 11 A. fumigatus isolates from patients with CAPA in three centres from different European countries and, carried out phenotypic analyses with a view to understand the pathophysiology of the disease. Our data indicates that A. fumigatus CAPA isolates are genomically diverse but are more similar to each other in their responses to infection-relevant stresses.

cell biology↗
bioRxiv2022

Functional characterization of the RNA interference pathway in A. fumigatus reveals its potential for antifungal therapy

The RNA interference (RNAi) pathway has evolved numerous functionalities in eukaryotes, with many on display in Kingdom Fungi. RNAi can regulate gene expression, facilitate drug resistance, or even be altogether lost to improve growth potential in some fungal pathogens. In the WHO fungal priority pathogen, Aspergillus fumigatus, the RNAi system is known to be intact and functional. To extend our limited understanding of A. fumigatus RNAi, we first investigated the genetic variation in RNAi-associated genes in a collection of 217 environmental and 83 clinical genomes, where we found that RNAi components are conserved even in clinical strains. Using endogenously expressed inverted-repeat transgenes complementary to a conditionally essential gene (pabA) or a nonessential gene (pksP), we determined that a subset of the RNAi componentry is active in inverted-repeat transgene silencing in conidia and mycelium. Analysis of mRNA-seq data from RNAi double-knockout strains linked the A. fumigatus dicer-like enzymes (DclA/B) and RNA-dependent RNA polymerases (RrpA/B) to regulation of conidial ribosome biogenesis genes; however, surprisingly few endogenous small RNAs were identified in conidia that could explain this broad change. Although RNAi was not clearly linked to growth or stress response defects in the RNAi knockouts, serial passaging of RNAi knockout strains for six generations resulted in lineages with diminished spore production over time, indicating that loss of RNAi can exert a fitness cost on the fungus. Cumulatively, A. fumigatus RNAi appears to play an active role in defense against double-stranded RNA species alongside a previously unappreciated housekeeping function in regulation of conidial ribosomal biogenesis genes.

microbiology↗
bioRxiv2022

Distinct cohorts of Aspergillus fumigatus transcription factors are required for epithelial damage occurring via contact- or soluble effector-mediated mechanisms

Damage to the lung epithelium is a unifying feature of disease caused by the saprophytic fungus Aspergillus fumigatus. However, the mechanistic basis and the regulatory control of such damage is poorly characterized. Previous studies have identified A. fumigatus mediated pathogenesis as occurring at early ([≤] 16 hours) or late (>16 hours) phases of the fungal interaction with epithelial cells, and respectively involve direct contact with the host cell or the action of soluble factors produced by mature fungal hyphae. Both early and late phases of epithelial damage have been shown to be subject to genetic regulation by the pH-responsive transcription factor PacC. This study sought to determine whether other transcriptional regulators play a role in modulating epithelial damage. In particular, whether the early and late phases of epithelial damage are governed by same or distinct regulators. Furthermore, whether processes such as spore uptake and hyphal adhesion, that have previously been documented to promote epithelial damage, are governed by the same cohorts of epithelial regulators. Using 479 strains from the recently constructed library of A. fumigatus transcription factor null mutants, two high-throughput screens assessing epithelial cell detachment and epithelial cell lysis were conducted. A total of 17 transcription factor mutants were found to exhibit reproducible deficits in epithelial damage causation. Of these, 10 mutants were defective in causing early phase damage via epithelial detachment and 8 mutants were defective in causing late phase damage via epithelial lysis. Remarkably only one transcription factor, PacC, was required for causation of both phases of epithelial damage. The 17 mutants exhibited varied and often unique phenotypic profiles with respect to fitness, epithelial adhesion, cell wall defects, and rates of spore uptake by epithelial cells. Strikingly, 9 out of 10 mutants deficient in causing early phase damage also exhibited reduced rates of hyphal extension, and culture supernatants of 7 out of 8 mutants deficient in late phase damage were significantly less cytotoxic. Our study delivers the first high-level overview of A. fumigatus regulatory genes governing lung epithelial damage, suggesting highly coordinated genetic orchestration of host-damaging activities that govern epithelial damage in both space and time. Contribution to the Field StatementAspergillus fumigatus is a soil dwelling fungus that can cause lethal lung infections in individuals with a compromised immune system. Disease initiates with inhalation of the fungal spores, followed by growth of the fungus leading to destruction of the lung. Our understanding of the A. fumigatus genes and mechanisms driving lung damage leading to establishment of disease is limited. This study has identified the genes moderating lung damage by assessing 479 regulatory mutants of A. fumigatus for their ability to cause epithelial damage using a lung cell line model. We observed that distinct cohorts of transcriptional regulators are required for driving early, and late phases of epithelial damage and that early- and late-occurring damage are associated respectively with hyphal growth rates and secreted fungal products. This study is the first to reveal that mechanistically distinct programs of host damage elicited during early and late stage of fungal interaction with epithelial cells are genetically regulated via distinct cohorts of A. fumigatus transcription factors.

microbiology↗
bioRxiv2022

Every single conidium in Aspergillus fumigatus caspofungin tolerant strains are intrinsically caspofungin tolerant

Aspergillus fumigatus is a human fungal pathogen that causes a disease named aspergillosis. Echinocandins, such as the fungistatic drug caspofungin (CAS) are used as second-line therapy. Some A. fumigatus clinical isolates can survive and grow in higher CAS concentrations, a phenomenon known as "caspofungin paradoxical effect" (CPE). Here we investigate if CPE is due to a subpopulation of conidia produced by a CAS tolerant strain, indicative of a persistence phenotype or is caused by all the conidia which would be consistent with a tolerance phenotype. We evaluated 67 A. fumigatus clinical isolates for CPE growth and used a novel CPE Index (CPEI) classified them as CPE+ (CPEI [≥] 0.40) or CPE- (CPEI [≤] 0.20). Conidia produced by three CPE+ clinical isolates, CEA17 (CPEI=0.52), Af293 (CPEI=0.64), CM7555 (CPEI=0.58) all showed the ability to grow in high levels of CAS while all conidia produced by the CPE- isolate IFM61407 (CPEI=0.12) strain showed no evidence of tolerance. Given the importance of calcium/calcineurin/transcription factor CrzA pathway in CPE regulation, we also evaluated {Delta}crzAAf293 (CPE-) and {Delta}crzACEA17 (CPE+) conidia tolerance to CAS. All {Delta}crzACEA17 conidia showed CPE+ while 100 % of {Delta}crzAAf293 spores are CPE-. As all spores derived from an individual strain are phenotypically indistinct with respect to CPE it is likely that CPE is a genetically encoded adaptive trait that should be considered an antifungal tolerant phenotype. As the CPEI shows that the strength of the CPE is not uniform between strains we propose that the mechanisms that govern this phenomenon are multi-factorial.

microbiology↗
bioRxiv2022

Azole resistance associated regulatory motifs within the promoter of cyp51A in Aspergillus fumigatus

Aspergillus fumigatus is one of the deadliest fungal species causing hundreds of thousands of deaths each year. As azoles provide the preferred first-line option for treatment of Aspergillosis, the increase in rates of resistance and the poor therapeutic outcomes for those infected with a resistant isolate constitutes a serious global health threat. Azole resistance is frequently associated with specific tandem repeat duplications of a promoter element upstream of cyp51A, the gene which encodes the target for this drug class in A. fumigatus. This promoter element is recognized by the activating transcription factors SrbA and AtrR. This region also provides a docking platform for the CCAAT-binding-complex (CBC) and HapX that cooperate in the regulation of genes involved in iron-consuming pathways including cyp51A. Here, we studied the regulatory contribution of SrbA, AtrR, CBC and HapX binding sites on cyp51A expression and azole resistance during different iron availability employing promoter mutational analysis and protein/DNA interaction analysis. This strategy revealed iron status-dependent and -independent roles of these regulatory elements. We show that promoter occupation by both AtrR and SrbA is required for iron-independent steady-state transcriptional activation of cyp51A and its induction during short-term iron exposure relies on HapX binding. We further uncover the HapX binding site as repressor element the disruption of which elevates cyp51A expression and azole resistance regardless of iron availability.

molecular biology↗
bioRxiv2021

Aspergillus fumigatus ffmA encodes a C2H2-containing transcriptional regulator that modulates azole resistance and is required for normal growth

The production of a collection of disruption mutant strains corresponding to a large number of transcription factors from the filamentous fungal pathogen Aspergillus fumigatus has permitted rapid identification of transcriptional regulators involved in a range of different processes. Here we characterize a gene designated ffmA (favors fermentative metabolism) as an C2H2-containing transcription factor that is required for azole drug resistance and normal growth. Loss of ffmA caused cells to exhibit significant defects in growth, either under untreated or azole-challenged conditions. Loss of FfmA caused a reduction in expression of the AbcG1 ATP-binding cassette transporter, previousy shown to contribute to azole resistance. Strikingly, overproduction of the AtrR transcription factor gene restored a wild-type growth phenotype to a ffmA{Delta} strain. Overexpression of AtrR also suppressed the defect in AbcG1 expression caused by loss of FfmA. Replacement of the ffmA promoter with a doxycycline-repressible promoter restored near normal growth in the absence of doxycycline. Finally, chromatin immunoprecipitation experiments indicated that FfmA bound to its own promoter as well as to the abcG1 promoter. These data imply that FfmA and AtrR interact both with respect to abcG1 expression and also more broadly to regulate hyphal growth. ImportanceInfections associated with azole-resistant forms of the primary human pathogen, Aspergillus fumigatus, are associated with poor outcomes in patient populations. This makes analysis of the mechanisms underlying azole resistance of A. fumigatus a high priority. In this work, we describe characterization of a gene designated ffmA that encodes a sequence-specific transcriptional regulator. We identified ffmA in a screen of a collection of gene disruption mutant strains made in A. fumigatus. Loss of ffmA caused sensitivity to azole drugs and also a large reduction in normal growth. We found that overproduction of the AtrR transcription factor was able to restore growth to ffmA null cells. We provide evidence that FfmA can recognize promoters of genes involved in azole resistance as well as the ffmA promoter itself. Our data indicate that FfmA and AtrR interact to support azole resistance and normal growth.

microbiology↗
bioRxiv2021

Olorofim and the azoles are antagonistic in Aspergillus fumigatus and functional genomic screens reveal mechanisms of cross resistance.

Aspergillosis, in its various manifestations, is a major cause of morbidity and mortality. Very few classes of antifungal drugs have been approved for clinical use to treat these diseases and resistance to the first line therapeutic class, the triazoles, is increasing. A new class of antifungals that target pyrimidine biosynthesis, the orotomides, are currently in development with the first compound in this class, olorofim in late-stage clinical trials. In this study, we identify an antagonistic action of the triazoles on the action of olorofim. We show that this antagonism is the result of an azole induced upregulation of the pyrimidine biosynthesis pathway and regulation. Intriguingly, we show that loss of function in the higher order transcription factor, HapB a member of the heterotrimeric HapB/C/E (CBC) complex or the regulator of nitrogen metabolic genes AreA, leads to cross resistance to both the azoles and olorofim indicating that factors that govern resistance are under common regulatory control. However loss of azole induced antagonism requires decoupling of the pyrimidine biosynthetic pathway in a manner independent of the action of a single transcription factor. Our study provides a first insight into antagonism between the azoles and olorofim through dysregulation of the pyrimidine and ergosterol pathway, showing complex crosstalk between these two pathways.

microbiology↗
bioRxiv2021

Tracing patterns of evolution and acquisition of drug resistant Aspergillus fumigatus infection from the environment using population genomics

Infections caused by opportunistic fungal pathogens are increasingly resistant to first-line azole antifungal drugs. However, despite its clinical importance, little is known about the extent to which susceptible patients acquire infection from drug resistant genotypes in the environment. Here, we present a population genomic analysis of the mould Aspergillus fumigatus from across the United Kingdom and Republic of Ireland. First, we show occurrences where azole resistant isolates of near identical genotypes were obtained from both environmental and clinical sources, indicating with high confidence the infection of patients with resistant isolates transmitted from the environment. Second, we find that the fungus is structured into two clades ( A and B) with little interclade recombination and the majority of environmental azole resistance genetically clustered inside Clade A. Genome-scans show the impact of selective sweeps across multiple regions of the genome. These signatures of positive selection are seen in regions containing canonical genes encoding fungicide resistance in the ergosterol biosynthetic pathway, whilst other regions under selection have no defined function. Phenotyping identified genes in these regions that could act as modifiers of resistance showing the utility of reverse genetic approaches to dissect the complex genomic architecture of fungal drug resistance. Understanding the environmental drivers and genetic basis of evolving fungal drug resistance needs urgent attention, especially in light of increasing numbers of patients with severe viral respiratory tract infections who are susceptible to opportunistic fungal superinfections.

genomics↗