Bacteria deserves the nomination of the most ubiquitous forms of life, first of all due to their metabolic diversity which enables them to obtain carbon atoms and energy from practically everywhere on Earth.

This diversity-based feature is seen by many as the true nature of bacteria, which makes them the real synonym of ubiquity. As living solar cells, bacteria are ‘messengers’ of life and are regarded as ‘inventors’ of photosynthesis and therefore are responsible for the transformation of sunlight into chemical energy.