A Novel Radiation-Resistant Strain of Filobasidium sp. Isolated from the West Sea of Korea

Abstract

A novel radiation-resistant Filobasidium sp. yeast strain was isolated from seawater. Along with this strain, a total of 656 yeast isolates were purified from seawater samples collected from three locations in the West Sea of Korea and assessed for their radiation tolerance. Among these isolates, five were found to survive a 5 kGy radiation dose. The most radiationresistant strain was classified as Filobasidium sp. based on 18S rDNA sequence analysis and hence was named Filobasidium RRY1 (Radiation-Resistant Yeast 1). RRY1 differed from F. elegans, which is closely related to RRY1, in terms of the optimal growth temperature and radiation resistance, and was resistant to high doses of γ-ionizing radiation (D10: 6-7 kGy). When exposed to a high dose of 3 kGy irradiation, the RRY1 cells remained intact and undistorted, with negligible cell death. When these irradiated cells were allowed to recover, the cells fully repaired their genomic DNA within 3 h of growth recovery. This is the first report in which a radiation-resistant response has been investigated at the physiological, morphological, and molecular levels in a strain of Filobasidium sp.

Geography and environmental pressure are predictive of class‐specific radioresistance in black fungi

“…Our study confirms black fungi as excellent models for the study of the mechanisms used by eukaryotic cells to cope with ionizing radiation (Selbmann et al, 2018). We observed a general stunning radioresistance of most of the black fungi if compared with other microorganisms and some of them exceed the survival limits of the most radioresistant prokaryotic and eukaryotic forms of life, confirming black fungi among the most radioresistant microorganisms observed so far (e.g., Cox & Battista, 2005;Daly, 2009;Krisko & Radman, 2013;Pacelli et al, 2017Pacelli et al, , 2018aShuryak, 2019;Singh et al, 2013;Sukhi et al, 2009). However, it should be highlighted that the response to ionizing radiation in microorganisms can vary markedly with the cellular state and exposure conditions (Couceiro, et al, 2021;Hafer et al, 2010;Schultzhaus et al, 2020).…”

Geography and environmental pressure are predictive of class-specific radioresistance in black fungi

“…We observed a general stunning radioresistance of most of the black fungi if compared to other microorganisms and some of them exceed the survival limits of the most radioresistant prokaryotic and eukaryotic forms of life (e.g. Cox et al, 2005;Daly, 2009;Sukhi et al, 2009;Singh et al, 2013;Krisko, 2013;Shuryak, 2019b). However, it should be highlighted that the response to ionizing radiation in microorganisms can vary markedly with the cellular state and exposure conditions (Hafer et al, 2010;Schultzhaus et al, 2020;Couceiro et al, 2021).…”

Ride the dust: linking dust dispersal and spatial distribution of microorganisms across an arid landscape

“…3G). Members of this genus have been reported as radiation resistant (Singh, 2013). Yeasts belonging to the Naganishia were also found to be UV resistant and prone to atmospheric dispersion in arid environments (Schmidt et al ., 2017).…”