Genome sequence of Halobacterium species NRC-1

We report the complete sequence of an extreme halophile, Halobacterium sp. NRC-1, harboring a dynamic 2,571,010-bp genome containing 91 insertion sequ ences representing 12 families and organized into a large chromosome and 2 related minichromosomes.:The Halobacterium NRC-1 genome codes for 2,630 pre dicted proteins, 36% of which are unrelated to any previously reported. Ana lysis of the genome sequence shows the presence of pathways for uptake and utilization of amino acids, active sodium proton antiporter and potassium u ptake systems, sophisticated photosensory and signal transduction pathways, and DNA replication.: transcription, and translation systems resembling mo re complex eukaryotic organisms. Whole proteome comparisons show the defini te archaeal nature of this halophile with additional similarities to the Gr am-positive Bacillus subtilis and other bacteria. The ease of culturing Hal obacterium and the availability of methods for its genetic manipulation in the laboratory, including construction of gene knockouts and replacements, indicate this halophile can-serve as an excellent model system among the ar chaea.