Halophiles are extremophiles that have optimal growth in concentrations above 0.2M NaCl and some are known to thrive above 5M NaCl. The major habitats of halophilic microorganisms are salt water and soils. Enzymes from extremely halophilic bacteria constitute a fascinating example of biochemical adaptation. Amylases are starch degrading enzymes which hydrolyse starch molecules to give diverse products including dextrins and progressively smaller polymers composed of glucose units.