The genome and transcriptome of a newly described psychrophilic archaeon, Methanolobus psychrophilus R15, reveal its cold adaptive characteristics

• Published in: Environmental Microbiology Reports
• Main Authors: Chen, Zijuan, Yu, Haiying, Li, Lingyan, Hu, Songnian, Dong, Xiuzhu
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2012
• Subjects: Antarctic; The Antarctic; Antarc*
• Online Access: http://dx.doi.org/10.1111/j.1758-2229.2012.00389.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1758-2229.2012.00389.x; http://onlinelibrary.wiley.com/wol1/doi/10.1111/j.1758-2229.2012.00389.x/fullpdf

Summary We analysed the cold‐responsive gene repertoire for a psychrophilic methanogen, M ethanolobus psychrophilus R 15 through genomic and RNA ‐seq assayed transcriptomic comparisons for cultures at 18° C (optimal temperature) versus 4° C . The differences found by RNA ‐seq analysis were verified using quantitative real time‐ PCR assay. The results showed that as in the Antarctic methanogen, M ethanococcoides burtonii , genes for methanogenesis, biosynthesis and protein synthesis were all downregulated by the cold in R 15. However, the RNA polymerase complex was upregulated at cold, as well as a gene cluster for a putative exosome complex, suggesting that exosome‐mediated RNA decay may be cold‐accelerated. Unexpectedly, the chaperonin genes for both thermosome and GroES / EL were all upregulated at 4° C . Strain R 15 possessed eight protein families for oxygen detoxification, including both anaerobe‐specific superoxide reductase ( SOR ) and the aerobe‐typical superoxide dismutase ( SOD )‐catalase oxidant‐removing system, implying the higher oxidative tolerance. Compared with a mesophilic methanogen, R 15 survived in higher paraquat, a redox‐cycling drug. Moreover, 71 one‐component systems and 50 two‐component systems for signal transduction ranked strain R 15, together with M . burtonii , as being highly adaptive among archaea. Most of them exhibited cold‐enhanced expression, indicating their involvement in cold adaptation. This study has added new perspectives on the cold adaptation of methanogenic archaea.