Adenosine triphosphate has three components
(a) Adenine (a nitrogen base)
(b) ribose sugar c) three inorganic phosphate. Adenine + ribose → Adenosine Adenosine + 3 Pi → Adenosine + triphosphate ATP can be written as A – (P) ~ (P) ~ (P).
The first phosphate which is linked by an ester linkage to ribose. The two-terminal bonds are energy-rich and first bond is energy poor. The energy-rich phosphate bonds are represented by a curly line (~) and energy-poor bond by a straight line (-). ATP is synthesized by the addition of inorganic phosphate to ADP. This process is Ceiled phosphorylation. n ADP + n Pi → n ATP.
There are three different types of phosphorylations.
- Photophosphorylation.
- Oxidative phosphorylation.
- Substrate level phosphorylation.
