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bioRxiv · 10.1101/2024.07.11.603131

Surviving the Storm: Exploring the Role of Natural Transformation in Nutrition and DNA Repair of Stressed Deinococcus radiodurans

Sharma, D. K.·Soni, I.·Gupta, G. D.·Rajpurohit, Y. S.
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Abstract

Deinococcus radiodurans, a natural transformation (NT) enabled bacterium renowned for its exceptional radiation resistance, employs unique DNA repair and oxidative stress mitigation mechanisms as a strategic response to DNA damage. This study excavate into the intricate roles of NT machinery in the stressed D. radiodurans, focusing on the genes comEA, comEC, endA, pilT and dprA, which are instrumental in the uptake and processing of extracellular DNA (eDNA). Our data reveals that NT not only supports the nutritional needs of D. radiodurans under stress but also have roles in DNA repair. The study findings establish that NT-specific proteins (ComEA, ComEC, and EndA) might contribute to support the nutritional requirements in unstressed and heavily DNA-damaged cells while DprA contribute differently and in a context-dependent manner to navigating through the DNA damage storm. Thus, this dual functionality of NT-specific genes is proposed to be one of factor in D. radiodurans remarkable ability to survive and thrive in environments characterized by high levels of DNA-damaging agents. Author SummaryDeinococcus radiodurans, a bacterium known for its extraordinary radiation resistance. This study explores the roles of natural transformation (NT) machinery in the radiation-resistant bacterium Deinococcus radiodurans, focusing on the genes comEA, comEC, endA, pilT, and dprA. These genes are crucial for the uptake and processing of extracellular DNA (eDNA) and contribute to the bacterium nutritional needs and DNA repair under stress. The findings suggest that the NT-specific proteins ComEA, ComEC, and EndA may help meet the nutritional needs of unstressed and heavily DNA-damaged cells, whereas DprA plays a distinct role that varies depending on the context in aiding cells to cope with DNA damage. The functionality of NT genes is proposed to enhance D. radiodurans survival in environments with high levels of DNA-damaging agents.

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Sharma, D. K., Soni, I., Gupta, G. D., Rajpurohit, Y. S.. 2024-07-12. Surviving the Storm: Exploring the Role of Natural Transformation in Nutrition and DNA Repair of Stressed Deinococcus radiodurans. https://doi.org/10.1101/2024.07.11.603131

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