Microbiology to 10,500 meters in the deep sea.

Microorganisms in the deep sea live at high pressures, low and high temperatures, and in darkness. These parameters and their food supply govern their lives. The study of these creatures gives us an opportunity to see how life processes work at some of the highest temperatures and pressures of the biosphere. Cultured bacterial isolates can grow to over 100 MPa at 2 degrees C and to over 40 MPa at over 100 degrees C. These cultures comprise the foundation for the study of the molecular biology and biotechnology of these isolates. The PTk diagram shows how temperature and pressure affect the growth rate of a bacterium and helps in the search for relationships among bacteria from habitats differing in temperature and pressure.