Biochemical activity of bacteria

Carbohydrate metabolism andterminal oxidation

Arash Ravandi

• All bacteria utilize energy sources to produce ATP.

• Source of energy for bacteria:C: from sugar and lipid → energy &

biosynthesisN: from protein → biosynthesisO: from air →energy

• Heterophilic bacteria use carbohydrate as energy source, they use enzymes to utilize simple sugars like glucose and monosaccharides

• Major carbohydrate metabolism pathway:• 1.Embden-meyerhof-parnas (EMP)

glycolysis• 2.Entner-Doudoroff (ED)• 3.Penthose phosphate (PP)• 4.Kreb´s cycle

• Each bacteria has it´s own collection of enzymesthis is useful to identify bacterial species by checking products from the oxidation and fermentation of these carbohydrates.

fermentation kit

Detection:• PH indicator: to detect metabolic acids

that produce by bacteria after oxidation and fermentation of sugars. Example: Phenol red

• Reagent: after bacteria have grown it reacts with specific byproduct or intermediates in the metabolic pathway.

• Gas production, Example: Durham tubes

Durham tube PH indicator

• Metabolic activity test:

ATP assay: measure ATP by luciferasesystem