Pyrosequencing is a
DNA sequencing method based on detecting the chemiluminescent signal emitted during the sequential addition of nucleotides. There are four major reactions involved in pyrosequencing, which are catalyzed four different
enzymes: DNA
polymerase, ATP sulfurylase,
luciferase and apyrase. Two substrates, adenosine 5´ phosphosulfate (APS) and luciferin, are also required in this process.