Unraveling adaptation of Pontibacter korlensis to radiation and infertility in desert through complete genome and comparative transcriptomic analysis.

The desert is a harsh habitat for flora and microbial life due to its aridness and strong radiation. In this study, we constructed the first complete and deeply annotated genome of the genus Pontibacter (Pontibacter korlensis X14-1(T) = CCTCC AB 206081(T), X14-1). Reconstruction of the sugar metabolism process indicated that strain X14-1 can utilize diverse sugars, including cellulose, starch and sucrose; this result is consistent with previous experiments. Strain X14-1 is also able to resist desiccation and radiation in the desert through well-armed systems related to DNA repair, radical oxygen species (ROS) detoxification and the OstAB and TreYZ pathways for trehalose synthesis. A comparative transcriptomic analysis under gamma radiation revealed that strain X14-1 presents high-efficacy operating responses to radiation, including the robust expression of catalase and the manganese transport protein. Evaluation of 73 novel genes that are differentially expressed showed that some of these genes may contribute to the strain's adaptation to radiation and desiccation through ferric transport and preservation.