Adenosinphosphate

Adenosinphosphate is a term used to refer to adenosine bound to one or more phosphate groups, forming the family of adenylates. The most common forms are adenosine monophosphate (AMP), adenosine diphosphate (ADP), and adenosine triphosphate (ATP). In each case, the adenosine moiety consists of the adenine base attached to a ribose sugar, with a chain of one to three phosphate groups linked to the 5' position of the ribose.

Biological roles: ATP functions as the primary energy currency of the cell, releasing energy when hydrolyzed to ADP or AMP and inorganic phosphate. ADP can be rephosphorylated to ATP, and AMP can be converted to ADP or restored to ATP via adenylate kinase and related pathways. AMP itself participates in energy sensing and signaling, for example via AMP-activated protein kinase (AMPK). Adenosine phosphates also serve as substrates for phosphorylation reactions in metabolism and signal transduction; cyclic adenosine monophosphate (cAMP) is a cyclic derivative that acts as a second messenger in many pathways.

Synthesis and metabolism: These molecules are produced and interconverted through kinases, ATP synthase, and various metabolic pathways. ATP is generated primarily by cellular respiration in mitochondria (oxidative phosphorylation) and, in photosynthetic organisms, by photophosphorylation.

Occurrence and applications: They are ubiquitous in biology, present in all living cells. In research and medicine, assays of ATP/ADP/AMP levels are used to assess cellular energy status; ATP is commonly used in enzyme assays and as an energy source in biotechnological processes.