The
complete genome sequence of the hyperthermophilic methanogen
Methanocaldococcus jannaschii has been determined.
The 1.66 Mb circular geonome of
M. jannaschii contains about
1800 genes, and from sequence analyses, genes encoding enzymes of methanogenesis and several other key cell functions have been identified.
Interestingly, the majority of
M. jannaschii genes encoding functions like central metabolic pathways and cell division are similar to those in
Bacteria, while most of the genes encoding core molecular processes like transcription and translation more closely resemble those of eukaryotes.
These findings support the
evolutionary tree of life that shows the domain
Archaea positioned between the domains
Bacteria and
Eukarya.
However, sequence analyses also showed that nearly 50% of
M. jannaschii genes have no counterparts in known genes from
Bacteria and
Eukarya, suggesting that there may be many new cellular functions encoded in archaeal DNA that have yet to be discovered.
For more information on
Methanocaldococcus jannaschii from
NCBI including updated sequence information,
click here.
Taken from the text Brock Biology of Microorganisms (10th ed.). Madigan, M.T., Martinko, J.M., and Parker, J. 2003. Prentice Hall. 455p.