Why is fungi important

A most interesting meta-study examined the enzymes produced and secreted in the fungus garden of the leaf cutter ant Grell et al. This showed that Leucoagaricus gongylophorus , farmed by leaf cutter ants, expressed the entire spectrum of enzymes needed for breaking down the cellulose fibres of the green leafy biomass which the ants bring to the fungal garden in their nest Fig. The ants pretreat by chewing the biomass.

The fungus expresses the needed regime of enzyme proteins. The enzymes even survive in an intact and active form passage through the gut channel of the ants. Redistribution of the enzymes to the newly harvested leafy biomass is achieved by the ants placing their enzymeholding fecalia on newly harvested leaves on the top of the fungus garden.

This entire sophisticated mutualistic system has been comprehensively described Kooij The fungus produces swollen tipped cells, filled with proteins and sugars, the gongylidia, organized in staphylae.

The gongylidia are picked by the ants for feeding the ant colony with protein and sugar rich feed. Bottom line is that this successful and complex society, where fungal enzymes convert green leaves into accessible, highly nutritious fungal biomass provide basis for one of the most successful life forms on earth.

Photo: Henrik H. De Fine Licht. In this interpretation the Leucoagaricus fungus is an example of a fungal adaptation path towards developing attractants to recruit insects to disperse the fungal spores as, for example, flies are attracted to the spore gleba of Phallus impudicus and thus lured into disseminating the fungal spores.

The ant-farmed L. It is the continuous supply of highly nutritious fungal gongylidia organized in bunches, the staphylae, readily harvestable by ants, which provides the basis for the ant colonies to grow to such size and societal complexity.

The global success of the ants is based on the fungal enzymes, the nutritional value of the fungal mycelium and the efficiency of the filamentous fungus growth and tip cells. We can learn from nature about how to construct biorefinery processes. The leaf cutter ant colony including the fungal garden can be seen as the archetype of a green biorefinery.

The cow rumen can be seen as a biorefinery for decomposing lignocellulosic straw, the yellow biorefinery. And the termite larvae gut channel can be seen as a biorefinery decomposing lignocellulosic woody materials. Interestingly, we also see that fungi are responsible for most of the lignocellulytic enzymes in most such biomass decomposing habitats in nature.

However, bacteria are always found in such biomass conversion niches and most likely are also playing a role in overall biomass conversion. There are many new examples in the pipeline of both academic and industrial research for upgrading the value of biomass and waste.

In the fungal garden of the ants, the fungus itself serves as highly nutritious animal feed! If more animal feed is produced based on the huge amounts of bio-waste we lose and discard along the chain from crop to food, and from the field to end user, we could release more land for biodiversity conservation and for food production FAO The latest research paves the way for making even more efficient use of the potential of biomass.

First, cellulose fibres are broken down to sugar monomers by fungal enzymes. Next in the value upgrade is using the sugar platform for growing microbes which produce building blocks for chemicals and for biopolymers, such as bioplastics.

The lignin will be developed into binders and materials still to be developed. And the hemicellulose polymer is processed by fungal enzymes for recovery of C 5 sugar oligosaccharides with prebiotic activity for a more healthy gut microbiota.

The ambition is to develop food ingredients which can make people more robust against life-style diseases and to develop animal feed for non-ruminant animals such as pigs with the prebiotic effect to improve metabolism. This gives better welfare and less need for antibiotic treatment — and limiting antibiotic use lowers the risk of runaway resistance to antibiotics.

All this is achievable by converting waste materials using fungal enzymes. The hemicellulose plant cell wall polymer, arabinoxylan, is degraded by many different and highly specialized fungal enzymes in nature: 1. Ongoing research aims to use such specific fungal enzymes to modify the arabinoxylan, a sub stream from lignocellulose biorefinery, into C 5 sugar oligosaccharides with a prebiotic effect, stimulating the healthy gut fungal and microbial populations of humans and other animals.

Modified from Chavez et al. The biotech industry has a good track record of using not just plant biomass but also fungal biomass directly as feed. The pigs loved it! Now a new approach is proposed. Transform sanitized household bio-waste into a fermentation medium, and use it as substrate for fungal growth.

From such a system the fungus biomass in itself, as a yeast cream, can be used as animal feed, which through fungal and bacterial biotransformation is one step removed from waste. With the available nitrogen supply the fungus will be able to develop into new nutritious protein-rich animal feed. Focused efforts will have to be made to optimize such a system, including optimizing the waste to fermentation medium process, for example by mixing different complementary and matching waste streams.

Research efforts have also been initiated with the objective of strain improvement to achieve an even higher nutritional value of the resulting fungal biomass. Two groups of fungi are being studied for this purpose: yeasts Saccharomyces cerevisiae or Candida utilis nonallergenic mutants and basidiomycetes such as those grown by termites Termitomyces , Fig.

Additional molecular studies can lead to even higher levels of fungal protein content and bio-accessibility. Learning from nature: the specialized basidiomycete Termitomyces titanicus Agaricales grows in subterranean termite nests. It can grow to form massive and impressive basidiomes, used as a human delicacy above. The benefit to the termites — even without having developed the sophisticated farming procedure — is accessibility to protein rich feed.

In future we will be able to make biorefineries by growing fungi on household waste and use the protein rich fungal biomass for animal feed. Photo and table: Duur Aanen.

Another potential way to extend conversion of biowaste for producing food and feed ingredients is to include animal derived materials, such as fish by-catch and waste as well as slaughter house waste such as pig bristles and chicken feathers Fig.

Another area where we need new enzymes is for the conversion of leftover press cake from production of plant oil from olive, palm tree, sunflower, rape, etc. This represents a substantial underexploited source of protein for both animal and human consumption. Onygena species. Non-pathogenic species of Onygenales , are specialized in breaking down the keratin found in feather, hooves, and horn. The keratin is composed of proteins, bound in a non-bio-accessible form.

Among the large number of different proteases produced by O. The picture shows O. Photo: Jens H. The affordable price of genome sequencing has made meta-studies of entire ecological niches doable, for example by metatranscriptomic or metagenomic sequencing, where an entire niche is handled as if it were one organism.

This approach enables inclusion of non-culturable organisms as well as all kinds of auxiliary enzymes we still are ignorant of. Another approach under development is to start including more than just ascomycetes and basidiomycetes in the enzyme discovery efforts. Interesting results are being gained right now from chytrids and zygomycetes, notably Entomophthorales Grell et al. As outlined above, the need for new enzymes is huge. Building the bioeconomy will include significant efforts in enzyme discovery to facilitate the diversification of substrates to be upgraded and of products to be developed from the biorefinery.

Such discovery efforts will simultaneously result in massive accumulation of underutilized genome sequencing data Murphy et al. The vision is straightforward: if we become better at predicting functions from sequences, we could significantly shorten and sharpen the enzyme discovery process.

We could go directly from sequence to the subgroup of enzyme genes we would like to screen to identify the one with the highest potential for that specific biomass conversion process. This list can be transformed into one providing an overview of all the functions illustrated as a list of EC numbers found in the secretome of that ecological niche. For each function, the protein families that have those functions, often more than one type of protein family for each EC function, can be speciied.

Another highly promising field for new microbial and fungal products is the use of inocula for strengthening crop plants, making the plants more robust to abiotic stress and more efficient with regard to water and nutrient utilization. Since the days of the green revolution, plant breeding has taken place almost in isolation except for breeding for increased tolerance against certain plant diseases and pests. Now, advances in the field of fungal and microbial products for agriculture is making it possible for plant breeders, mycologists, and microbiologists, to work together to find the combination of plants and other organisms which will provide farmers and the world with more robust and resilient agriculture.

At a time when climate change challenges agriculture in many parts of the world, and where water and nutrition are at a minimum in many places, the combinations of fungi, microbes, and plants can provide opportunities for significant progress in global food, feed, and biomass production.

It will be interesting to follow developments in this area. Again, a new field is emerging that builds on a platform of knowledge generated through the combined efforts of public and private mycological research, where fungi are seen as having the potential to contribute significantly towards a more sustainable world.

This is therefore a highly interesting area for contributions from mycologists specialized in endophytes, mycorrhizas, Penicillium, Aspergillus, Trichoderma, Fusarium , soil fungi, and consortia where bacteria and fungi work together to produce efficient and optimized systems. Next in demand are regimes of enzymes active under low temperature conditions and enzymes active and stable at high temperatures for decomposition of both plant and animal derived biomasses. Here, mycologists specialized in extremophiles can contribute significantly Zajc et al.

Could intensified studies of the archaean splicing mechanisms and protein expression lead to a breakthrough in the development of fungal production hosts for heat stable secreted enzymes from these microorganisms?

Improved expression of basidiomycete genes in ascomycetous expression hosts, such as yeasts, also builds on an improved understanding of the variations in protein expression mechanisms within the fungal kingdom. There are discoveries to be made of new kinds of antibiotics from fungal hotspots for antibiotics. Discovery of novel drug candidates with new modes of action and central nervous system active metabolites from fungi, which manipulate insects to adopt behavioral patterns that optimize the chances for dispersal of fungus spores formed on the insect after the insect dies e.

Maybe such research efforts can reveal new concepts for neurosignalling, induced in animals, based on stimuli given by fungal metabolites or proteins, but which may also be of relevance for increased understanding of the human central nervous system? This is important because there will be a steep increase in amounts of fungal biomass available for upgrade as the technology of biomass conversion in biorefineries develops.

In nature, complex patterns and mechanisms of collaboration are expected to occur especially between fungi and bacteria. There are also fungi that partner with mammals, living inside their guts and helping them to digest; and others that partner with algae and bacteria — including some that allow certain extremophile bacteria to live in hot springs and withstand scalding temperatures. In addition to forging individual relationships with plants and keeping Earth tidy, fungi collectively have broader relevance to keeping our planet habitable.

This is a not insignificant function; land is the second-largest carbon sink on Earth, after the ocean, holding almost 30 percent of what we store for a massive climate benefit. Fungi also contribute to keeping the temperature of our planet in balance. They do this by emitting CO2 — although, with climate change rapidly heating up our atmosphere, researchers are trying to better understand how fungi and climate might now be affecting each other.

In fact, not knowing permeates many aspects of mycology. As Bhatnagar explains, only a couple hundred fungal species have so far been scientifically described and although we are getting better at figuring out how they work — alone, in groups with other fungi, with plants, and so forth — there are still massive question marks regarding much of the Kingdom and how it operates. Leaving these questions unanswered could have dire consequences for our planetary systems and our food supply.

For example, hyphae can remain alive in wood chips used for mulching, and the mulch you purchase at the nursery could have originated almost anywhere.

These are not just broad philosophical concerns. Meanwhile, the books below will get you up to speed on identifying fungi species, including those that are good to eat, as well as cooking and storing them, growing them, and thinking about their numerous uses to humans and our planet.

This field guide geared towards absolute beginners offers myriad photographs to help you locate and identify fungi in the wild. In addition to providing a reference to some North American species, two brief chapters cover cultivating fungi as well as cooking what you grow and find — with recipes. All life on land, including my own, depended on these networks. This is a great next step along your educational journey. Together or individually, you can pore over the informative text to learn about mushroom habitats and ecosystems.

Or just spend hours gazing at the intricate and mesmerizing illustrations. Trends Plant Sci. Deacon, L. Diversity and function of decomposer fungi from a grassland soil. Delgado-Baquerizo, M. Circular linkages between soil biodiversity, fertility and plant productivity are limited to topsoil at the continental scale. New Phytol. Dengler, J. Biodiversity of Palaearctic grasslands: a synthesis.

Ding, J. Influence of inorganic fertilizer and organic manure application on fungal communities in a long-term field experiment of Chinese Mollisols. Doran, J. Doran and A. Doran, D. Coleman, D. Bezdicek, and B. El-Komy, M. Characterization of novel Trichoderma asperellum isolates to select effective biocontrol agents against tomato Fusarium wilt. Plant Pathol.

Ferris, H. Unearthing the role of biological diversity in soil health. Occurrence, detection, and molecular and metabolic characterization of heat-resistant fungi in soils and plants and their risk to human health.

Microbial functional diversity in podzol ectohumus horizons affected by alkaline fly ash in the vicinity of electric power plant. Microbial community diversity and the interaction of soil under maize growth in different cultivation techniques.

Plant Soil Environ. Gardi, C. Soil Biodiversity. Brussels: European Commission, Geiser, D. Girisha, G. Decomposition and nutrient dynamics of green and freshly fallen radiata pine Pinus radiata needles. Gonzalez, M. Tobacco leaf spot and root rot caused by Rhizoctonia solani Kuhn. Goss, M. Soil disturbance reduces the efficacy of mycorrhizal associations for early soybean growth and N2 fixation. Gweon, H.

PIPITS: an automated pipeline for analyses of fungal internal transcribed spacer sequences from the Illumina sequencing platform. Methods Ecol. Hannula, S. Shifts in rhizosphere fungal community during secondary succession following abandonment from agriculture.

ISME J. Primer sets developed for functional genes reveal shifts in functionality of fungal community in soils. Hesse, C. Forest floor community metatranscriptomes identify fungal and bacterial responses to N deposition in two maple forests. Extramatrical ectomycorrhizal mycelium contributes one-third of microbial biomass and produces, together with associated roots, half the dissolved organic carbon in a forest soil.

Huhe, Y. Bacterial and fungal community structures in loess plateau grasslands with different grazing intensities. Jayne, B. Influence of arbuscular mycorrhiza on growth and reproductive response of plants under water deficit: a meta-analysis.

Mycorrhiza 24, — Land Degrad. Johnson, D. Plant communities affect arbuscular mycorrhizal fungal diversity and community composition in grassland microcosms.

Joubert, L. Applied vegetation science 20 — moderate grazing sustains plant diversity in Afromontane grassland. Kibblewhite, M. Soil health in agricultural systems. B Biol. Klosterman, S. Diversity, pathogenicity, and management of Verticillium species. Kurakov, A. Changes in the composition and physiological and biochemical properties of fungi during passage through the digestive tract of earthworms. Leff, J. Consistent responses of soil microbial communities to elevated nutrient inputs in grasslands across the globe.

Lindahl, B. Liu, J. Soil carbon content drives the biogeographical distribution of fungal communities in the black soil zone of northeast China. Trichoderma as biostimulant: exploiting the multilevel properties of a plant beneficial fungus. Lucas, R. Soil microbial communities and extracellular enzyme activity in the New Jersey Pinelands. Winter wheat yield and soil properties response to long-term non-inversion tillage.

Michielse, C. Pathogen profile update: Fusarium oxysporum. Morrien, E. Soil networks become more connected and take up more carbon as nature restoration progresses. Nguyen, N. FUNGuild: an open annotation tool for parsing fungal community datasets by ecological guild. Fungal Ecol. Doctoral dissertation, Stockholm University, Stockholm. Pal, A. Biosorption of cobalt by fungi from serpentine soil of Andaman. PubMed Abstract Google Scholar.

Phosri, C. Diversity and community composition of ectomycorrhizal fungi in a dry deciduous dipterocarp forest in Thailand. Porras-Alfaro, A. Diversity and distribution of soil fungal communities in a semiarid grassland. Mycologia , 10— From genus to phylum: large-subunit and internal transcribed spacer rRNA operon regions show similar classification accuracies influenced by database composition.

Prosser, J. Replicate or lie. Rillig, M. Mycorrhizas and soil structure. Rouphael, Y. Arbuscular mycorrhizal fungi act as biostimulants in horticultural crops. Salter, S. Reagent and laboratory contamination can critically impact sequence-based microbiome analyses. BMC Biol. Schoch, C. Schoenholtz, S.

A review of chemical and physical properties as indicators of forest soil quality: challenges and opportunities. Analysis of soil microbial communities based on amplicon sequencing of marker genes.