Question

The synthesis of ATP (phosphorylation) occurs as a means of trapping energy released by metabolic reactions. 3 general mechanisms of phosphorylation are listed below. Define and distinguish between these 3 mechanisms. For each mechanism, identify a metabolic reaction that involves that type of phosphorylation and identify a group of microbes that carry out that metabolic reaction.

• Substrate-level phosphorylation
• Oxidative phosphorylation
• Photophosphorylation                                                                         

Answer 1

Substrate level phosphorelation is the process of synthesis of ATP from phosphate group.The way it achieves energy from phosphate group is by the transfer phosphate group from higher energy substrate to lower energy component. It also absorbs energylike gibbs energyfor the synthesis of ATP. Some examples of the microbes that use Substrate level phosphorelation are Clostridium and Phosphorylation.

Oxidative phosphorylaton is mainly the process of synthesis of ATP by NADH and FADH. The enzyme breaks the oxygen molecule which inturn releases chemical energy which is required for the ATP synthesis. Nitrobacter is example for a microbe which synthesises ATP by Oxydative phosphorelation

In photophosphorylation, the synthesis of ATP from ADP is done by photosynthes. The energy required to do photophosphorylation is gained from sunlight and the cyclic anaerobic oxydation-reduction reactions. someof the examples are algae and cyanobacteria