U.S. and German researchers have discovered a unique fungal protein capable of freezing water at relatively warmer subzero temperatures. This breakthrough opens up exciting possibilities for safer cloud seeding, enhanced climate models, and innovative advancements in food preservation and medicine.
Mortierellomycetes and Umbelopsidomycetes fungi from freshwater ecosystems in Korea. Image credit: Goh et al., doi: 10.4489/kjm.20230018.
In cloud seeding, particles known as ice nucleators are introduced into clouds to promote the transformation of cloud water into ice crystals.
As more water molecules adhere to these crystals, they grow in size.
This process creates a snowball effect, where ice crystals become heavier, descend to the ground, and melt into rain as they traverse the atmosphere.
Typically, conventional ice nucleators like silver iodide are used, which are highly toxic.
Professor Boris Binatzer and his team at Virginia Tech suggest that these fungal protein molecules could present a safer alternative.
“If we can efficiently produce these fungal proteins in large quantities, we could enhance cloud seeding safety,” Professor Binatzer stated.
The researchers also uncovered that the fungal genes responsible for ice nucleation proteins likely originated from bacterial species through horizontal gene transfer, a process that occurred hundreds of thousands of years ago.
“While we know fungi can acquire bacterial genes, this isn’t commonplace,” explains Professor Binatzer.
Since the early 1990s, researchers have been aware of fungi’s ability to form ice nuclei. Recent advancements in DNA sequencing and computational biology have enabled the sequencing of genomes from a specific fungal family, Mortierellaceae, revealing the genes coding for ice nucleation proteins.
The function of the acquired genes for fungi is still unclear, but it is evident they have enhanced their capabilities over time.
This genetic modification offers significant human benefits.
The ice-nucleating proteins produced by fungi are distinct from those produced by bacteria in that they are cell-free and water-soluble.
These characteristics make fungal molecules highly attractive for bioinspired refrigeration technologies and artificial weather manipulation.
For instance, in frozen food production, fungal molecules present a safer option compared to bacterial ones since fungi only secrete ice-nucleating proteins, eliminating the need for entire bacterial cells.
“This is a major advantage in food production, allowing use of a single well-defined protein while omitting unnecessary components,” Professor Vinatzer added.
“We have the potential to create safe and effective additives for frozen food preparation.”
Additionally, fungal ice nucleation may prove beneficial in the cryopreservation of cells such as tissues, sperm, eggs, and embryos.
“Utilizing fungal ice nucleators—relatively small molecules—enables faster freezing of water around cells, safeguarding delicate cellular structures,” stated Professor Binatzer.
“This approach is not feasible with bacteria since the entire bacterial cell must be added.”
Ice nucleation plays a crucial role in climate models, impacting predictions of how much radiation is reflected back into space by clouds versus what reaches Earth. Ice presence in clouds allows more radiation to reach our planet.
With the identification of these fungal molecules, determining their quantity in clouds becomes more manageable.
In the long term, this pioneering research could significantly enhance climate modeling accuracy.
For further details, refer to the study findings published in the journal Scientific Progress.
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Rosemary J. Eufemio et al. 2026. A previously unrecognized class of fungal ice nucleoproteins with bacterial ancestry. Scientific Progress 12(11); doi: 10.1126/sciadv.aed9652
Source: www.sci.news
