Recovery of halophilic archaebacteria from natural environments

Media of various compositions were employed to recover halophilic archaebacteria from a variety of naturally occurring thalassohaline environments, including saturated brines and stromatolithic algal mats. Maximum recovery rates were obtained on media containing natural brine and a whole cell extract of Halobacterium cutirubrum. These rates were up to 10²-fold higher than rates obtained on media prepared with either component alone and up to 10⁷-fold higher than rates obtained on conventional media. Enhanced recovery in the presence of natural brine and H. cutirubrum extract was due to those constituents allowing the bacteria present in situ to adapt to growth on laboratory media. However, several isolates demonstrated an absolute requirement for a factor present in both H. cutirubrum extract and natural brine.