Biology subjects

Hayes, R. D.

Publications and source records attributed to Hayes, R. D..

4 recordsLinked to original sources

bioRxiv2024

Hydrophobins from Aspergillus mediate fungal interactions with microplastics

Microplastics present myriad ecological and human health risks including serving as a vector for pathogens in human and animal food chains. However, the specific mechanisms by which pathogenic fungi colonize these microplastics have yet to be explored. In this work, we examine the opportunistic fungal pathogen, Aspergillus fumigatus, and other common soil and marine Aspergilli, which we found bind microplastics tightly. Up to 3.85+/-1.48 g microplastic plastic/g fungi were bound and flocculated for polypropylene (PP), polyethylene (PE), and polyethylene terephthalate (PET) powders and particles ranging in size from 0.05 - 5 mm. Gene knockouts revealed hydrophobins as a key biomolecule driving microplastic-fungi binding. Moreover, purified hydrophobins were still able to flocculate microplastics independent of the fungus. Our work elucidates a role for hydrophobins in fungal colonization of microplastics and highlights a potential target for mitigating the harm of microplastics through engineered fungal-microplastic interactions. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=107 SRC="FIGDIR/small/622132v1_ufig1.gif" ALT="Figure 1"> View larger version (33K): org.highwire.dtl.DTLVardef@13eb679org.highwire.dtl.DTLVardef@3dc9c0org.highwire.dtl.DTLVardef@888c96org.highwire.dtl.DTLVardef@c5e1aa_HPS_FORMAT_FIGEXP M_FIG C_FIG Significance StatementMicroplastics pose serious ecological and human health effects by introducing pathogens and toxins into animal and human food chains. Many pathogenic microorganisms preferentially form biofilms on microplastic particles that are then ingested. Here, we demonstrate that hydrophobins, highly hydrophobic, cell surface proteins, enable microplastic binding and colonization by the opportunistic pathogen Aspergillus fumigatus and other fungi within the Aspergillus genus. Our work recognizes a novel role for hydrophobin proteins, identifying potential strategies for pathogen control and protein-based microplastics recovery.

molecular biology↗

bioRxiv2024

High phenotypic and genotypic plasticity among strains of the mushroom-forming fungus Schizophyllum commune

Schizophyllum commune is a mushroom-forming fungus notable for its distinctive fruiting bodies with split gills. It is used as a model organism to study mushroom development, lignocellulose degradation and mating type loci. It is a hypervariable species with considerable genetic and phenotypic diversity between the strains. In this study, we systematically phenotyped 16 dikaryotic strains for aspects of mushroom development and 18 monokaryotic strains for lignocellulose degradation. There was considerable heterogeneity among the strains regarding these phenotypes. The majority of the strains developed mushrooms with varying morphologies, although some strains only grew vegetatively under the tested conditions. Growth on various carbon sources showed strain-specific profiles. The genomes of seven monokaryotic strains were sequenced and analyzed together with six previously published genome sequences. Moreover, the related species Schizophyllum fasciatum was sequenced. Although there was considerable genetic variation between the genome assemblies, the genes related to mushroom formation and lignocellulose degradation were well conserved. These sequenced genomes will provide a solid basis for functional genomics analyses of the strains of S. commune.

microbiology↗

bioRxiv2023

Conservation and Expansion of Transcriptional Factor Repertoire in the Fusarium oxysporum Species Complex

The Fusarium oxysporum species complex (FOSC) includes both plant and human pathogens that cause devastating plant vascular wilt diseases and threaten public health. Each F. oxysporum genome comprises core chromosomes (CCs) for housekeeping functions and accessory chromosomes (ACs) that contribute to host-specific adaptation. This study inspected global transcription factor profiles (TFomes) and their potential roles in coordinating CCs and ACs functions to accomplish host-specific pathogenicity. Remarkably, we found a clear positive correlation between the sizes of TFome and proteome of an organism, and FOSC TFomes are larger due to the acquisition of ACs. Among a total of 48 classified TF families, 14 families involved in transcription/translation regulations and cell cycle controls are highly conserved. Among 30 FOSC expanded families, Zn2-C6 and Znf_C2H2 are most significantly expanded to 671 and 167 genes per family, including well-characterized homologs of Ftf1 (Zn2-C6) and PacC (Znf_C2H2) involved in host-specific interactions. Manual curation of characterized TFs increased the TFome repertoires by 3%, including a disordered protein Ren1. Expression profiles revealed a steady expression of conserved TF families and specific activation of AC TFs. Functional characterization of these TFs could enhance our understanding of transcriptional regulation involved in FOSC cross-kingdom interactions, disentangle species-specific adaptation, and identify targets to combat diverse diseases caused by this group of fungal pathogens.

genomics↗

bioRxiv2023

Chromosome-level genomes of multicellular algal sisters to land plants illuminate signaling network evolution

The filamentous and unicellular algae of the class Zygnematophyceae are the closest algal relatives of land plants. Inferring the properties of the last common ancestor shared by these algae and land plants allows us to identify decisive traits that enabled the conquest of land by plants. We sequenced four genomes of filamentous Zygnematophyceae (three strains of Zygnema circumcarinatum and one strain of Z. cylindricum) and generated chromosome-scale assemblies for all strains of the emerging model system Z. circumcarinatum. Comparative genomic analyses reveal expanded genes for signaling cascades, environmental response, and intracellular trafficking that we associate with multicellularity. Gene family analyses suggest that Zygnematophyceae share all the major enzymes with land plants for cell wall polysaccharide synthesis, degradation, and modifications; most of the enzymes for cell wall innovations, especially for polysaccharide backbone synthesis, were gained more than 700 million years ago. In Zygnematophyceae, these enzyme families expanded, forming co-expressed modules. Transcriptomic profiling of over 19 growth conditions combined with co-expression network analyses uncover cohorts of genes that unite environmental signaling with multicellular developmental programs. Our data shed light on a molecular chassis that balances environmental response and growth modulation across more than 600 million years of streptophyte evolution. HIGHLIGHTSO_LIGenomes of four filamentous algae (Zygnema) sisters to land plants C_LIO_LIZygnema are rich in genes for multicellular growth and environmental acclimation: signaling, lipid modification, and transport C_LIO_LICell wall innovations: diversification of hexameric rosette cellulose synthase in Zygnematophyceae C_LIO_LICo-expression networks reveal conserved modules for balancing growth and acclimation C_LI

evolutionary biology↗