ANALYSIS OF THE GENOME OF THE GRAM-NEGATIVE MODERATE HALOPHILES HALOMONAS AND CHROMOHALOBACTER BY USING PULSED-FIELD GEL-ELECTROPHORESIS

The genomes of 11 moderately halophilic bacteria belonging to the gene ra Halomonas and Chromohalobacter have been analyzed by restriction en donuclease digestion and pulsed-field gel electrophoresis (PFGE). By u sing the infrequently cutting restriction endonucleases SpeI and SwaI, highly characteristic fingerprintings were obtained for each of the i solates studied. On the basis of the lengths of the SpeI and SwaI frag ments, separated by PFGE, the genome size of the 11 strains studied wa s estimated. The genome size for 8 Halomonas strains ranged from 1450 to 2830 kb, whereas for the 3 Chromohalobacter strains studied it rang ed from 1770 to 2295 kb. Finally, we show that macrorestriction finger prints could be a useful tool to elucidate the taxonomic position of b acteria belonging to the Halomonas-Deleya complex.