Isolation of Cave Bacteria and Substrate Utilization at Different Temperatures

Bacteria isolated from the soils of three northern Spain caves were investigated for their growth at temperatures in the range 5-45°C, substrate utilization pattern, and cellular fatty acid components. All tested bacteria were able to grow comparatively well in a range of temperatures from 13° to 45°C. At 13°C the bacteria oxidized on average 87% of carbon sources provided while incubation at 28°C reduced to about 50% carbon source utilization. Changes in fatty acid profiles reflected an adaptative response to temperature. The results suggest the need of using low temperatures to detect maximum diversity of culturable bacteria (other than actinomycetes) and efficiency of carbon utilization by cave bacteria.