Abstract
Recently, huge numbers of bacteria kilometres deep in the Earth have been discovered. These bacteria may represent over 50% of all life on Earth. But we know almost nothing about these bacteria as we can only grow a tiny fraction of them in the laboratory for study. Deep ocean sediments contain most of these deep biosphere bacteria and here pressures are enormous over 300 times that at the surface. Up till now the only way to study them was by bringing samples to the surface and trying to study them at atmospheric pressure, which might kill the vast majority of them. We have developed a system which enables bacteria to be consistently grown and studied under high pressure. This can be used with a new pressure coring and handling system so that bacteria are never depressurised which should allow deep bacteria not previously seen to be studied. We will investigate these bacteria to find out what type they are, how they survive in their extreme (high pressure, low energy and zero oxygen) environment and how they might influence processes in deep sediments and rocks which were previously thought to be geological environments devoid of life. These deep sediments can be tens of millions of years old and may contain ancient bacteria. They may even be an environment where life on Earth might have started. So understanding these bacteria will not only tell us about life on Earth it might also tell us more about how life began.
United Kingdom