MOTILITY AND THERMOTACTIC RESPONSES OF THERMOTOGA-MARITIMA

Thermotoga maritima, a thermophilic eubacterium, is motile at temperat ures ranging from 50 to 105 degrees C. The cells are propelled by a si ngle flagellum which most of the time spins clockwise. Changes in the swimming direction (''tumbles'') are achieved by short reversals of th e direction of filament rotation. The average speed of swimming cells depends on the temperature, reaching a maximum value of about 60 mu m/ s at 85 degrees C. The cells show a thermotactic response to temporal temperature changes. When the temperature is raised, the rate of tumbl es is increased, while decreasing temperature decreases the tumbling r ate.