2,6-Diaminopurine

2,6-Diaminopurine (2,6-DAP) is a compound once used in the treatment of leukemia. 2,6-Diaminopurine (2,6-DAP) is a compound once used in the treatment of leukemia. In August 2011, a report, based on NASA studies with meteorites found on Earth, was published suggesting 2,6-diaminopurine and related organic molecules, including the DNA and RNA components adenine and guanine, may have been formed extraterrestrially in outer space. In cyanophage S-2L, diaminopurine is used instead of adenine (host evasion). Diaminopurine basepairs perfectly with thymine as it is identical to adenine but has an amine group at position 2 forming 3 intramolecular hydrogen bonds, eliminating the major difference between the two types of basepairs (weak:A-T and strong:C-G). This improved stability affects protein-binding interactions that rely on those differences.