Bacterial Metabolism

 Bacterial Metabolism:

Introduction:

Metabolism refers to all the biochemical reactions that occur in a cell or organism.The study of bacterial metabolism focuses on the chemical diversity of substrate oxidations and dissimilation reactions ,which normally function in bacteria to generate energy.metabolism has an energy-generating component, called catabolism (exergonic), and an energyconsuming, biosynthetic component, called anabolism (andergonic).Catabolic reactions or sequences produce energy as ATP, which can be utilized in anabolic reactions to build cell material from nutrients in the environment.

Metabolic pathways of energy generation (ATP)

Carbohydrates (particularly glucose), lipids, and protein are the most commonly oxidized compounds.

Biologic oxidation of these organic compounds by bacteria results in synthesis of ATP as the chemical energy source.

This process also permits generation of simpler organic compounds (precursor molecules) needed by the bacteria cell for biosynthetic or assimilatory reactions.

Carbohydrate Catabolism

Glucose oxidation is the most commonly studied dissimilatory reaction leading to energy production or ATP synthesis.

The complete oxidation of glucose may involve three fundamental biochemical pathways.

Ø  Glycolytic or Embden- Meyerhof-Parnas pathway

Ø  Krebs cycle

Ø  Membrane-bound electron transport oxidations coupled to oxidative phosphorylation.

Glycolysis

Glucose is the most common substrate used for studying heterotrophic metabolism.

. Heterotrophic bacteria, which include all pathogens, obtain energy from oxidation of organic compounds.

Electron transport chain

Cellular Respiration and fermentation:

Fermentation:

Lipid Catabolism

Protein Catabolism