Editing Nucleoside triphosphate (section)

== Naming ==
The term [[nucleoside]] refers to a [[nitrogenous base]] linked to a 5-carbon sugar (either [[ribose]] or [[deoxyribose]]).<ref name=":0" /> [[Nucleotide]]s are nucleosides [[covalently]] linked to one or more [[phosphate group]]s.<ref>{{cite book| vauthors = Lodish H, Berk A, Zipursky SL, Matsudaira P, Baltimore D, Darnell J |date=2000|title=Structure of Nucleic Acids|url=https://www.ncbi.nlm.nih.gov/books/NBK21514/}}</ref> To provide information about the number of phosphates, nucleotides may instead be referred to as nucleoside (mono, di, or tri) phosphates.<ref name=":1">{{cite journal | vauthors = Secrist JA | title = Nucleoside and nucleotide nomenclature | journal = Current Protocols in Nucleic Acid Chemistry | volume = Appendix 1 | pages = A.1D.1–A.1D.3 | date = May 2001 | pmid = 18428808 | doi = 10.1002/0471142700.nca01ds00 | hdl = 2027.42/143595 | s2cid = 205152902 | url = https://deepblue.lib.umich.edu/bitstream/2027.42/143595/1/cpnca01d.pdf | hdl-access = free }}</ref> Thus, nucleoside triphosphates are a type of nucleotide.<ref name=":1" />

Nucleotides are commonly abbreviated with 3 letters (4 or 5 in case of deoxy- or dideoxy-nucleotides). The first letter indicates the identity of the nitrogenous base (e.g., A for [[adenine]], G for [[guanine]]), the second letter indicates the number of phosphates (mono, di, tri), and the third letter is P, standing for phosphate.<ref>{{Cite web|url=http://www.biochem.uthscsa.edu/med/02-Nucleotide-Metab/PrereqNucleotideMetab3.html|title=Nomenclature of Nucleosides|website=www.biochem.uthscsa.edu|access-date=2017-11-11}}</ref> Nucleoside triphosphates that contain [[ribose]] as the sugar are conventionally abbreviated as NTPs, while nucleoside triphosphates containing [[Deoxyribose|<u>d</u>eoxyribose]] as the sugar are abbreviated as dNTPs. For example, dATP stands for deoxyribose adenosine triphosphate. NTPs are the building blocks of [[RNA]], and dNTPs are the building blocks of [[DNA]].<ref>{{Cite news|url=https://science-explained.com/theory/dna-rna-and-protein/|title=From DNA to RNA to protein, how does it work?|work=Science Explained|access-date=11 November 2017}}</ref> 
The carbons of the sugar in a nucleoside triphosphate are numbered around the carbon ring starting from the original [[Carbonyl group|carbonyl]] of the sugar. Conventionally, the carbon numbers in a sugar are followed by the prime symbol (‘) to distinguish them from the carbons of the nitrogenous base. The nitrogenous base is linked to the 1’ carbon through a [[glycosidic bond]], and the phosphate groups are covalently linked to the 5’ carbon.<ref>{{Cite web|url=http://www.biosyn.com/tew/numbering-convention-for-nucleotides.aspx|title=Numbering convention for nucleotides |website=www.biosyn.com|access-date=2017-11-11}}</ref> The first phosphate group linked to the sugar is termed the α-phosphate, the second is the β-phosphate, and the third is the γ-phosphate; these are linked to one another by two [[High-energy phosphate|phosphoanhydride]] bonds.<ref>{{cite web | url = http://www.sparknotes.com/biology/molecular/dnareplicationandrepair/section2.rhtml|title=SparkNotes: DNA Replication and Repair: The Chemistry of the Addition of Substrates of DNA Replication|website=www.sparknotes.com|access-date=2017-11-11}}</ref>[[File:Nucleotides 1.svg|thumb|670x670px|Schematic showing the structure of nucleoside triphosphates. Nucleosides consist of a 5-carbon sugar (pentose) connected to a nitrogenous base through a 1' glycosidic bond. Nucleotides are nucleosides with a variable number of phosphate groups connected to the 5' carbon. Nucleoside triphosphates are a specific type of nucleotide. This figure also shows the five common nitrogenous bases found in DNA and RNA on the right. |center]]