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Biology subjects

Bonito, G.

Publications and source records attributed to Bonito, G..

8 recordsLinked to original sources

Biosynthetic additive manufacturing through mycelium-bacteria consortia

Lignocellulosic biomass is the most abundant renewable raw material on Earth, yet its structural and carbon-storage potential remains unrealized: microbial decomposition returns stored carbon to the atmosphere before it can be harnessed as a durable material. Distinct microbial processes, such as biosynthesis and biomineralization, offer a natural counterpoint, converting organic carbon into mechanically robust, persistent materials such as polymers and minerals. Here, we establish a biosynthetic additive manufacturing strategy through mycelium-bacteria consortia, by coupling fungal self-assembly with bacterial biomineralization inside fabricated three-dimensional scaffolds derived from lignocellulosic biomass. Trametes versicolor forms a continuous living mycelial network that serves as both a structural template and a transport pathway, guiding the spatial colonization of Sporosarcina pasteurii and enabling volumetric calcium carbonate deposition throughout the scaffold interior, overcoming the surface-limited mineralization of conventional microbial systems. Integration with helicoidal Bouligand architectures translates microscale mineral reinforcement into macroscale performance, increasing compressive Young's modulus by 7-14-fold and ultimate strength by 5-fold relative to unmineralized conventional mycelium-based living composites. The living mycelial network also enables autonomous self-healing and modular self-assembly through hyphal bridging without external adhesives or energy input. This work establishes a scalable route for converting and upcycling transient biomass carbon into durable living structural materials for sustainable construction.

bioengineering↗

A Caulobacter hub taxon in the soybean root endosphere has a distinctive biofilm and engages in riboflavin-mediated mutualism with Bradyrhizobium

While it is well established that communities of microbes colonize the surfaces of plants as epiphytes and the interior plant tissues as endophytes, their ecological roles and colonization mechanisms remain under characterized. Members of the genus Caulobacter have emerged as hub taxa in epiphytic and endophytic microbiomes of diverse plant hosts, but the factors that support their colonization and community interactions have not been defined. Here, we characterize Caulobacter sp. RL271, a non-canonical member of the genus recently identified as a hub taxon in the soybean root endosphere. We demonstrate that the surface attachment strategies and biofilm architecture of Caulobacter sp. RL271 are determined by a matrix of capsular polysaccharide and cellulose rather than a polar holdfast adhesin, a classical defining feature of the genus. Both polysaccharide components influence the kinetics of plant root colonization in the model plant Arabidopsis thaliana. We further demonstrate that the ecology of Caulobacter sp. RL271 is shaped by its nutritional dependence on exogenous riboflavin and by interactions with Bradyrhizobium diazoefficiens, the nitrogen-fixing symbiont of soybean roots. This work advances understanding of Caulobacter biology and establishes RL271 as a tractable model for dissecting the functional role of hub taxa in root endophyte communities.

microbiology↗

Mycoelectronics: Bioprinted Living Fungal Bioelectronics for Artificial Sensation

The intelligence of the human biological system is enabled by the highly distributed sensing receptors on soft skin that can distinguish various stimulations or environmental cues, thus establishing the fundamental logic of sensing and physiological regulation or response. To replicate biological perception, two approaches have emerged: artificial nervous systems that utilize soft electronics as biomimetic receptors to convert external stimuli into frequency-encoded signals, and biohybrid solutions that integrate living cells, plants, or even live animals with electronic components to decode environmental cues for life-like sensations. However, most current biohybrid approaches for artificial sensation are based on eukaryotic cells, which suffer from slow growth, stringent culture conditions, environmental susceptibility, and short lifespans, thus limiting their integration into practical wearables or robotic sensory skins. Here, we introduce fungi-based printable "Mycoelectronics", which are created by additive bioprinting of living fungal mycelium networks onto stretchable electronics, as a practical living thermo-responsive sensory platform. This Mycoelectronics approach leverages fungis capacity for rapid biological responsiveness, cultivability with exponential growth, stability and self-healing in ambient conditions, bioprintability for scalable manufacturing, and mechanical flexibility for seamless integration with soft electronics. Critically, we discovered that the thermal responsiveness of the fungal network arises from intrinsic cellular processes--specifically, heat-induced vacuole remodeling and fusion, which modulate ionic transport and thus the electrical conductivity of the mycelial cells and networks, enabling a rapid temperature response. By bridging the gap between cell biology and soft electronics, the Mycoelectronics device with a living mycelium network functions as a thermal sensation system with rapid response and intrinsic self-healing properties, autonomously restoring sensing capabilities after damage or autonomously establishing sensor pathways in hard-to-reach locations. Furthermore, by integrating fungal thermal sensing with electronic circuits, we established a hybrid bioelectronic reflex arc that can actuate muscles and initiate diverse actions, suggesting promising applications in future neurorobotics and neuroprosthetics.

bioengineering↗

Genetic modification of the shikimate pathway to reduce lignin content in switchgrass (Panicum virgatum L.) significantly impacts plant microbiomes

Switchgrass (Panicum virgatum L.) is considered a sustainable biofuel feedstock, given its fast-growth, low input requirements, and high biomass yields. Improvements in bioenergy conversion efficiency of switchgrass could be made by reducing its lignin content. Engineered switchgrass that expresses a bacterial 3-dehydroshikimate dehydratase (QsuB) has reduced lignin content and improved biomass saccharification due to the rerouting of the shikimate pathway towards the simple aromatic protocatechuate at the expense of lignin biosynthesis. However, the impacts of this QsuB trait on switchgrass microbiome structure and function remains unclear. To address this, wildtype and QsuB engineered switchgrass were grown in switchgrass field soils and samples were collected from inflorescences, leaves, roots, rhizospheres, and bulk soils for microbiome analysis. We investigated how QsuB expression influenced switchgrass-associated fungal and bacterial communities using high-throughput Illumina MiSeq amplicon sequencing of ITS and 16S rDNA. Compared to wildtype, QsuB engineered switchgrass hosted different microbial communities in roots, rhizosphere, and leaves. Specifically, QsuB engineered plants had a lower abundance of arbuscular mycorrhizal fungi (AMF). Additionally, QsuB engineered plants had fewer Actinobacteriota in root and rhizosphere samples. These findings may indicate that changes in the plant metabolism impact both organismal groups similarly, or potential interactions between AMF and the bacterial community. This study enhances understanding of plant-microbiome interactions by providing baseline microbial data for developing beneficial bioengineering strategies and by assessing non-target impacts of engineered plant traits on the plant microbiome.

microbiology↗

Linnemannia elongata (Mortierellaceae) stimulates Arabidopsis thaliana aerial growth and responses to auxin, ethylene, and reactive oxygen species

Harnessing the plant microbiome has the potential to improve agricultural yields and protect plants against pathogens and/or abiotic stresses, while also relieving economic and environmental costs of crop production. While previous studies have gained valuable insights into the underlying genetics facilitating plant-fungal interactions, these have largely been skewed towards certain fungal clades (e.g. arbuscular mycorrhizal fungi). Several different phyla of fungi have been shown to positively impact plant growth rates, including Mortierellaceae fungi. However, the extent of the plant growth promotion (PGP) phenotype(s), their underlying mechanism(s), and the impact of bacterial endosymbionts on fungal-plant interactions remain poorly understood for Mortierellaceae. In this study, we focused on the symbiosis between soil fungus Linnemannia elongata (Mortierellaceae) and Arabidopsis thaliana (Brassicaceae), as both organisms have high-quality reference genomes and transcriptomes available, and their lifestyles and growth requirements are conducive to research conditions. Further, L. elongata can host bacterial endosymbionts related to Mollicutes and Burkholderia. The role of these endobacteria on facilitating fungal-plant associations, including potentially further promoting plant growth, remains completely unexplored. We measured Arabidopsis aerial growth at early and late life stages, seed production, and used mRNA sequencing to characterize differentially expressed plant genes in response to fungal inoculation with and without bacterial endosymbionts. We found that L. elongata improved aerial plant growth, seed mass and altered the plant transcriptome, including the upregulation of genes involved in plant hormones and "response to oxidative stress", "defense response to bacterium", and "defense response to fungus". Furthermore, the expression of genes in certain phytohormone biosynthetic pathways were found to be modified in plants treated with L. elongata. Notably, the presence of Mollicutes- or Burkholderia-related endosymbionts in Linnemannia did not impact the expression of genes in Arabidopsis or overall growth rates.

plant biology↗

Biochar alters soil properties, microbial community diversity, and enzyme activities, while decreasing conifer performance

Biochars are porous charcoal-like materials that can enhance soil health and plant growth, but its use has not been adequately evaluated in woody cropping systems. We set up an experimental Christmas tree plantation on a Marlette series soil amended with two types of biochar and conducted two studies on the impacts of biochar on the agroecosystem over three years following establishment. The first study investigated the effects of biochar on plant performance, soil physicochemical properties and extracellular enzyme activities, while the second investigated the response of the root-associated fungal community. Both biochars stimulated five extracellular enzyme activities, with increases of between 67% and 446%. Structural equation modelling identified increases to dissolved organic carbon and soil moisture as potential mechanisms of biochars effects on enzyme activities. Tree growth and survival were negatively affected by biochar application, depending on the tree species and biochar applied, which may have been due to induced nitrogen limitation. High-throughput sequencing showed that biochar decreased the diversity of root-associated fungal communities, with the ectomycorrhizal species Wilcoxina mikolae reaching levels of hyper-dominance on balsam fir in response to one of the biochars. Further studies should investigate how biochar can be harnessed to remediate specific soil quality issues or restructure soil ecosystems in ways that improve crop performance.

ecology↗

Host genetic control of succession in the switchgrass leaf fungal microbiome

Leaf fungal microbiomes can be fundamental drivers of host plant success, as they contain pathogens that devastate crop plants and taxa that enhance nutrient uptake, discourage herbivory, and antagonize pathogens. We measured leaf fungal diversity with amplicon sequencing across an entire growing season in a diversity panel of switchgrass (Panicum virgatum). We also sampled a replicated subset of genotypes across three additional sites to compare the importance of time, space, ecology, and genetics. We found a strong successional pattern in the microbiome shaped both by host genetics and environmental factors. Further, we used genome-wide association mapping and RNA-sequencing to show that three cysteine-rich receptor-like kinases were linked to a genetic locus associated with microbiome structure. These genes were more highly expressed in genotypes susceptible to fungal pathogens, which were central to microbial covariance networks, suggesting that host immune genes are a principal means of controlling the entire leaf microbiome.

ecology↗

CONSTAX2: Improved taxonomic classification of environmental DNA markers

CONSTAX - the CONSensus TAXonomy classifier - was developed for accurate and reproducible taxonomic annotation of fungal rDNA amplicons and is based upon a consensus approach of RDP, SINTAX and UTAX algorithms. CONSTAX2 can be used to classify prokaryotes and incorporates BLAST-based classifiers to reduce classification errors. Additionally, CONSTAX2 implements a conda-installable, command line tool with improved classification metrics, faster training, multithreading support, capacity to incorporate external taxonomic databases, new isolate matching and high-level taxonomy tools, replete with documentation and example tutorials. Availability and ImplementationCONSTAX2 is available at https://github.com/liberjul/CONSTAXv2, and is packaged for Linux and MacOS from Bioconda. A tutorial and documentation are available at https://constax.readthedocs.io/en/latest/.

bioinformatics↗