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  • Crusty-Pinky: A Novel Polyextremotolerant Fungus and its Methylobacterium Symbionts Could be an Essential Symbiosis for the Biological Soil Crust Consortium

This content will become publicly available on February 12, 2026

Title: Crusty-Pinky: A Novel Polyextremotolerant Fungus and its Methylobacterium Symbionts Could be an Essential Symbiosis for the Biological Soil Crust Consortium
JF2 08-2F Crusty is a novel melanized polyextremotolerant fungus isolated from a biological soil crust, which we believe harborsMethylobacteriumspp. endosymbionts, called Pinky. Crusty is capable of utilizing many sources of carbon and nitrogen and is resistant to multiple metals and UV-C due to its melanized cell wall. We were unable to recover a Pinky-free culture of Crusty via usage of antibiotics. However, when exposed to antibiotics that kill or stop the growth of the Pinky, growth of Crusty is significantly stunted, implying that actively growing Pinky symbionts are needed for Crusty’s optimal growth. The Crusty-Pinky symbiosis also seems to be able to perform active metabolism in carbonless and nitrogenless medium, which we believe is due to Pinky’s ability to perform aerobic anoxygenic photosynthesis. Finally, Pinky was identified as being capable of growth stimulation of the algaeChlorella sorokiniana, indicating that Pinky likely produces cytokinins or auxins whichMethylobacteriumare known for. Features of this symbiosis provide us insight into the ecological roles of these microbes within the biological soil crust.  more » « less
Award ID(s):
2209217
PAR ID:
10575107
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
bioRxiv
Date Published:
Format(s):
Medium: X
Institution:
bioRxiv
Sponsoring Org:
National Science Foundation
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