What is the Classification of Bacteria on the Basis of Nutrition?

Bacteria can be classified based on their mode of nutrition. It can be classified into autotrophic, heterotrophic, saprophytic, and parasitic groups based on their mode of nutrition. This classification system helps to understand the diverse nutritional requirements of different types of bacteria and their ecological roles.

The following are the major classifications of bacteria based on their nutrition:

  • Autotrophic bacteria: Autotrophic bacteria are those that can synthesize their own organic compounds from inorganic sources, such as carbon dioxide and water, using energy from the environment. There are two types of autotrophic bacteria: (a) Photoautotrophs, which use light as an energy source and (b) Chemoautotrophs, which use energy from chemical reactions to synthesize organic compounds.
  • Heterotrophic bacteria: Heterotrophic bacteria are those that obtain their nutrition from organic compounds that are synthesized by other organisms. There are two types of heterotrophic bacteria: (a) Photoheterotrophs, which use light energy to break down organic compounds, and (b) Chemoheterotrophs, which obtain their energy from chemical reactions.
  • Saprophytic bacteria: Saprophytic bacteria obtain their nutrition by decomposing dead organic matter. These bacteria play a vital role in the ecosystem by breaking down complex organic compounds into simpler compounds that can be used by other organisms.
  • Parasitic bacteria: Parasitic bacteria obtain their nutrition from a living host organism. These bacteria are pathogenic and can cause various diseases in plants and animals, including humans.