The discovery of giant viruses has been a fascinating area of research in recent years. These massive microorganisms can infect amoebas and other microscopic organisms, and their life cycles and distribution are still not well understood. A new study from the University of Jyväskylä, Finland, has shed light on this hidden world by isolating a giant virus from Finnish soil. The virus, named Jyvaskylavirus, is about twice the size of influenza or coronavirus and has been found to be related to previously isolated viruses in France.

Giant viruses are more common than researchers had thought, particularly in northern regions like Finland. They play an essential role in regulating microbial populations in soil and water. The discovery of Jyvaskylavirus highlights the importance of studying these microorganisms further to understand their interactions with other living organisms.

Professor Lotta-Riina Sundberg from the University of Jyväskylä led the study, which involved isolating giant viruses from environmental samples mixed with a culture of amoeba Acanthamoeba castellanii. The team’s findings demonstrate that giant viruses are more prevalent in soil and water than previously thought.

The discovery will have significant implications for our understanding of microbial ecosystems and the role of viruses in regulating populations of all living organisms. It also highlights the importance of further research into the structure and function of giant viruses, such as Jyvaskylavirus.

As researchers continue to explore this uncharted territory, they may uncover even more fascinating secrets about the microscopic world we inhabit. The study of giant viruses is a reminder that there is still much to learn from these tiny but mighty microorganisms.

Industrial farming practices often rely on artificial fertilizers to support crop growth, depleting soil nutrients and polluting the environment. However, researchers at the Salk Institute are proposing a new solution that leverages the natural symbiosis between plants and beneficial fungi. By boosting this relationship through the supplementation of plant peptides called CLE16, farmers may be able to encourage crop growth without the need for chemical fertilizers.

The study, published in The Proceedings of the National Academy of Sciences, found that CLE16 promotes a mutually beneficial relationship between plants and arbuscular mycorrhizal fungi. These fungi supply plants with water and phosphorus, while the plants provide carbon molecules to the fungi. This exchange occurs through specialized fungal tendrils that bury themselves into plant root cells.

Senior author Lena Mueller notes that many plants have evolved to engage in symbiotic relationships with other species, but industrial breeding techniques have weakened these traits in modern-day crops. By restoring this natural symbiosis, researchers hope to help crops get the nutrients they need without the use of harmful fertilizers.

In their study, Mueller’s lab started by growing a species of arbuscular mycorrhizal fungus together with Medicago truncatula, a small Mediterranean legume. They found that once the two had formed a symbiotic relationship, the plants began to express large amounts of CLE16, a signaling molecule that promotes symbiosis.

The researchers then added excess CLE16 to the soil and observed that it caused the fungal arbuscules to become more robust and live longer, ultimately increasing the abundance of these nutrient-trading structures in the roots. This created a self-amplifying pro-symbiosis signal, where the more beneficial fungus expanded inside the roots, the more CLE16 was produced by the plant.

The team also discovered that many arbuscular mycorrhizal fungi produce their own CLE16-like peptides, which promote symbiosis when added to the soil. These fungal peptides imitate the plants’ own CLE16 peptides, allowing the beneficial fungus to amplify symbiosis by binding to the same plant CRN-CLAVATA receptor complexes.

With validation that both plant CLE16 and fungal CLE16-like peptide supplementation improved symbiosis, researchers believe that similar supplementation on farmland may be the solution to kick-starting the growth of fungal networks that benefit crops year after year. Future work will validate whether CLE16 peptides or fungal CLE16-like peptide mimics also promote symbiosis in important crops like soy, corn, or wheat.

If successful, harnessing these molecules could replace unsustainable chemical fertilizers with beneficial fungi, making our crops, fields, and soils more sustainable and healthier in the long run.

The use of antifungal agents in agriculture may be contributing to the growing problem of resistance among infectious yeasts, according to a recent study published in PLOS Biology. Researchers from Fudan University, China, have found that exposure to tebuconazole, a common agricultural fungicide, can lead to genomic changes in Candida tropicalis yeast cells, making them resistant to antifungals.

Candida tropicalis is one of the most common fungi to infect humans, and while many infections are treatable, some can be life-threatening, especially among people who are immunocompromised. As more fungi become increasingly resistant to antifungal medicines, the need for understanding the biological mechanisms underlying this resistance has become crucial.

The study revealed that when C. tropicalis was exposed to tebuconazole, its cells’ genomes became unstable and lost half their DNA. It was previously thought that these yeast required two copies of each chromosome to survive (diploid), but the researchers found that haploid cells (with one copy of each chromosome) persisted and were resistant to antifungals.

While it is unclear exactly how this change in chromosomes creates antifungal resistance, the study provides evidence that agriculture’s use of antifungals may be a key factor in the increasing levels of resistance seen among C. tropicalis and other infectious yeasts, such as Candida auris. This “superbug” fungal pathogen has emerged as a significant concern due to its ability to evade antifungal treatments.

The authors emphasize that this study highlights the importance of considering agriculture’s use of antifungals when addressing the growing problem of resistance among infectious fungi. By understanding the mechanisms underlying this resistance, researchers and policymakers can work together to develop effective strategies for mitigating this issue and ensuring public health.