AraATP

araATP, also known as arabinose triphosphate, is a non-canonical nucleoside triphosphate. Unlike the standard deoxyribonucleotides (dATP, dCTP, dGTP, dTTP) and ribonucleotides (ATP, CTP, GTP, UTP) that form the building blocks of DNA and RNA, araATP incorporates arabinose as its sugar moiety instead of ribose or deoxyribose. This structural difference significantly impacts its biochemical properties and biological roles.

araATP is primarily recognized as a substrate for certain DNA polymerases, particularly those involved in repairing DNA damage or processing specific DNA structures. It can be incorporated into DNA strands, leading to chain termination or altered DNA stability depending on the polymerase and the context of incorporation. This property has led to its investigation as a potential chemotherapeutic agent, as its incorporation can disrupt DNA replication and cell proliferation in rapidly dividing cancer cells.

While not a standard component of cellular metabolism, araATP can arise endogenously through various pathways, or be supplied exogenously. Its presence and activity are often studied in the context of DNA repair mechanisms and the development of novel antiviral and anticancer drugs. Research continues to explore the precise mechanisms by which araATP interacts with cellular machinery and its potential therapeutic applications.