Draft Genome Sequence of the Thermoalkaliphilic

The genes and molecular machines that allow for a thermoalkaliphilic lifestyle have not been defined. To address this goal, we report on the improved high-quality draft genome sequence of Caldalkalibacillus ther-marum strain TA2.A1, an obligately aerobic bacterium that grows optimally at pH 9.5 and 65 to 70°C on a wide variety of carbon and energy sources. Thermoalkaliphilic microorganisms are poorly understood as a group, and there is very little information available on the genes and molecular machines that allow for a thermoalkali-philic lifestyle. To live at high pH and temperature, akin to a proton desert, these bacteria must overcome a number of ther-modynamic challenges. These include capturing and retaining protons from an alkaline environment (pH 9.5) to drive endo-thermic reactions in the cell membrane (2), increased mem-brane permeability to protons at high temperature (16), and a low protonmotive force that appears to be suboptimal for growth (12). Studies of the membrane-bound F1Fo-ATP syn