PHYLOGENETIC DIVERSITY OF SODA LAKE ALKALIPHILES

16S rRNA genes from a range of aerobic chemoorganotrophic, alkaliphili c soda lake Bacteria and Archaea have been sequenced and subjected to phylogenetic analysis. Gram-negative alkaliphiles were found to be con fined to the gamma 3 subdivision of the Proteobacteria, with many isol ates related to the Halomonas/Deleya group. Gram-positive alkaliphiles were found in both high % G + C and low % G C C divisions of the Gram -positive lineage, with many isolates being related to the Bacillus gr oup, others to Arthrobacter spp. Alkaliphilic Archaea were relatively closely related to members of the genera Natronococcus and Natronobact erium. An anaerobic, thermophilic isolate has been assigned to a new g enus within the Thermotogales.