Structural features and functional implications of proteins enabling the robustness of Deinococcus radiodurans

Abstract

Deinococcus radiodurans can survive under extreme conditions, including high doses of DNA damaging agents and ionizing radiation, desiccation, and oxidative stress. Both the efficient cellular DNA repair machinery and antioxidation systems contribute to the extreme resistance of this bacterium, making it an ideal organism for studying the cellular mechanisms of environmental adaptation. The number of stress-related proteins identified in this bacterium has mushroomed in the past two decades. The newly identified proteins reveal both commonalities and diversity of structure, mechanism, and function, which impact a wide range of cellular functions. Here, we review the unique and general structural features of these proteins and discuss how these studies improve our understanding of the environmental stress adaptation mechanisms of D. radiodurans.

Keywords: Antioxidation; DNA repair; Deinococcus; Manganese; Metal ion; Zinc.

Fig. 1

Illustration of the structures of stress-related proteins in Deinococcus species. (A–D) Protein domains from monomeric proteins are shown in distinct colors. ssDNA and the C-terminal region of drSSB protein in (A) are colored red and magenta, respectively. dsDNA in (C) is colored red. (E–M) Protomers from protein homo-oligomer structures are distinctively colored based on protein self-assembly. ssDNA in (E) is colored red. Their PDB accession codes are shown and references can be found in the Table 1. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)