kemotrófia

Chemotrophy is a metabolic strategy employed by living organisms to obtain energy. Unlike phototrophs, which derive energy from light, chemotrophs utilize chemical compounds as their energy source. This process involves the oxidation of electron donors, which are typically organic or inorganic substances. The released energy is then used to synthesize adenosine triphosphate (ATP), the primary energy currency of the cell.

Chemotrophs are broadly categorized into two groups based on their electron donors. Chemoorganotrophs obtain energy by oxidizing organic compounds, such as sugars, fats, and alcohols. This is the most common form of energy metabolism found in many bacteria, archaea, and eukaryotes. Chemoautotrophs, on the other hand, derive energy from the oxidation of inorganic compounds. Examples of inorganic electron donors include hydrogen sulfide, ammonia, ferrous iron, and molecular hydrogen. These organisms are often found in environments where organic matter is scarce, such as deep-sea hydrothermal vents or subsurface rocks.

The specific chemical reactions involved in chemotrophy vary widely depending on the organism and the electron donor. However, the fundamental principle remains the same: the transfer of electrons from a reduced compound to an oxidant, coupled with the generation of ATP. Chemotrophy plays a crucial role in various biogeochemical cycles, contributing to the cycling of elements like carbon, nitrogen, and sulfur within ecosystems.