Genomic organization of the halophilic archaeon Haloferax mediterranei: physical map of the chromosome

Pulsed field gel electrophoresis (PFG) has been used to study the genomic organization of the halophilic archaeon Haloferax mediterranei</it>. Analysis of the different genomic elements as well as the restriction patterns obtained with several endonucleases revealed that this microorganism has a circular chromosome of 2.9 Mb and, at least, three extrachromosomal elements of 490, 320 and 130 kb respectively. The complete physical map of the chromosome for the endonucleases PacI</it> and BamHI</it> has been constructed, and several BcII</it>, BgIII</it> and DraI</it> restriction fragments have been aligned on these maps. The localization of heterologous and homologous genes on the physical map, including those for rRNA, lay the ground work for the construction of a genetic map.