Exploring the structural landscape of universal stress proteins in Archaea.

The universal stress protein (USP) superfamily is widely distributed in the three domains of life. These proteins play a key role in the cell response to biotic and abiotic stresses. Although the discovery of the first USP was more than 30 years ago, little is known about its specific function and the molecular mechanisms underlying it. Focusing on the Archaea domain, USPs represent one of the mechanisms developed to survive under environmental stresses, such as nutritional deprivation, oxidative stress, or heavy metal toxicity. This review provides a comprehensive understanding of USPs in this domain, with a focus on their structure and function. It delves into the distribution of USPs in several families of Archaea and explores the structures of selected USPs, paying special attention to those of halophilic and thermophilic microorganisms. Additionally, the biotechnological implications of USPs in Archaea are examined, highlighting their potential in protein engineering and the development of novel biotechnological applications. Understanding the structure and function of USPs will expedite the development of improved industrial processes and contribute to the advancement of innovative medical therapies.