CHANGED METABOLISM. “In many organisms, there is an upregulation of genes involved in glycolysis, gluconeogenesis and glycogen metabolism during a high pressure exposure, also accompanied by high ATP levels. This could be explained as a stress response and a reflection of the need to rapidly manage energy and osmotic stability.”
http://www.quora.com/What-are-the-biochemical-adaptations-that-piezophiles-make-to-protect-their-proteins-lipids-DNA