adenosine triphosphate

Adenosine triphosphate (ATP) is a cell's charged storage unit for energy.

When its energy is spent it becomes Adenosine diphosphate (ADP). The ADP can then be recharged and reused indefinitely.

Cells take in energy units such as glucose and break them down into carbon dioxide, water, and energy. The energy released is used to hook a phosphate group to the ADP, recharging it and making it into ATP again; this can then be broken back down by the cell to give off the stored energy.

Even more energy can be extracted by removing a second phosphate group, creating adenosine monophosphate (AMP). Breaking ATP directly into AMP will create a pyrophosphate, which is unstable and will break down very quickly, making the ATP --> AMP reaction irreversible. (The ATP --> ADP --> AMP reaction does not create a pyrophosphate, and is reversible).

The human body contains about 0.1 mole of ATP; the energy used by the body's cells requires the hydrolysis of 200 to 300 moles of ATP each day. Each ATP molecule is recycled 2000 to 3000 times every day. Every hour about 1 kilogram of ATP is created, processed, and recycled in your body.

Its full chemical name is [[[5-(6-aminopurin-9-yl)-3,4-dihydroxy-oxolan-2-yl] methoxy-hydroxy-phosphoryl] oxy-hydroxy-phosphoryl] oxyphosphonic acid.

It's usually referred to as ATP.

The chemical formula is C₁₀H₁₆N₅O₁₃P₃

Its molecular mass is 507.181 g mol^-1

Its CAS number is 56-65-5

ATP->ADP+P+Energy

$ - high energy single-bond

                             -.
            NH2               |
            |                 |
       N == C                 |
      /      \                |
H -- C        C -- N          |
      \\     //     \\        |
       N -- C        C -- H   |
              \     /         |
                 N            |
                 |             }- adenosine
                 C            |
                /  \          |
         OH -- C-H  \         |
               |     O        |
         OH -- C-H  /         |
                \  /          |
                 C   H        |
                / \ /         |
               H   C -- H     |             
                   |          |
                   O         -'
                   |         -. -. -.
             OH -- P == O      }-+--|- monophosphate (AMP)
                   |          |  |  |
                   O         -'  |  |
                   $             |  |
             OH -- P == O         }-+-- diphosphate (ADP)
                   |             |  |
                   O            -'  |
                   $                |
             OH -- P == O            }- triphosphate (ATP)
                   |                |
                   O               -'
                    

ATP is the pricipal energy carrying molecule of all cells and is indespensable to the life of the cell.

It stores the chemical energy released by some chemical reaction, and it provides the energy for further reactions.

It consists of adenosine unit, composed of adenine and ribose, with three phosphate groups attached.

It is called a high energy molecule because it releases a large amount of usable energy when hydrolyzed to become adenosine diphosphate (ADP)

Adenosine_Phosphate_Phosphate_Phosphate + H20 ---> Adenosine_Phosphate_Phosphate_inorganicPhosphate + ENERGY

Adenosine Triphosphate consists of adenine (an organic base) and ribose (a pentose sugar) together with three phosphate groups. ATP is therefore a small, water-soluble nucleotide which can be easily transported around the cell.

When a phosphate group is removed from ATP, adenosine diphosphate (ADP) is formed and 30.5 kJmol^-1 of energy is released.

ATP + H₂O <--> ADP + H₃PO₄ ± 30.5 kJmol^-1

ATP can be considered an energy currency in which the cell deals

ATP is a molecule which consists of the nitrogenous base adenine linked to the sugar ribose and which has a chain of three phosphate groups attached to the ribose in a linear fashion.

ATP is present in all living cells and serves as an energy source for many metabolic processes; energy is released when ATP is hydrolyzed into ADP. ATP is required for ribonucleic acid synthesis since it is a direct precursor. It is the single most important molecule in all living things since it serves as the currency for energy in biological systems.

From the BioTech Dictionary at http://biotech.icmb.utexas.edu/. For further information see the BioTech homenode.