Adenosine triphosphate (ATP) is a nucleotide that performs multiple functions. Its most important function is to transfer chemical energy meant to be used for metabolic activities. It is produced during cellular respiration and is utilized by enzymes as well as during processes such as biosynthetic reactions and cell divisions. Karl Lohmann discovered adenosine triphosphate in 1929 and its main function of being an energy-transfer molecule was suggested by Fritz Albert Lipmann in 1941.