By comparative sequence analysis with methanogen genomes, including those of the mesophile Methanosarcina barkeri (Tmax: 40oC), the thermophile Methanosarcina thermophila (Tmax: 55oC) and the extreme thermophile Methanococcus jannaschii (Tmax: 85oC) it will be possible to identify a subset of genes unique to the cold-adapted methanogen. In silico protein structure comparisons may also highlight adaptive strategies. In addition to the evolutionary implications inherent with comparing mechanisms of archaeal cold-adaptation with those in Bacteria and Eukarya, completion of the M. burtonii genome sequence will expand our understanding of the organismal and metabolic biocomplexity that has evolved in association with cold-adapted microorganisms. Completing the genomic sequence of this extremophile will contribute to the long-term goal of establishing the global cold-adaptive strategies of microorganisms and defining the boundaries of life on Earth and in extraterrestrial environments. References Franzmann, P.D.,
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PD. Nichols PD. 1998. CARBON ISOTOPIC FRACTIONATION ASSOCIATED WITH
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