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thymine
thymine , organic base of the pyrimidine family. Thymine was the first pyrimidine to be purified from a natural source, having been isolated from calf thymus and beef spleen in 1893-4. The accepted structure of the thymine molecule was published in 1900; this structure was confirmed when several investigators reported the synthesis of the compound during the period 1901 to 1910. Combined with the sugar deoxyribose in a glycosidic linkage, thymine forms a derivative called thymidine (a nucleoside), which in turn can be phosphorylated with from one to three phosphoric acid groups, yielding respectively the three nucleotides TMP (thymidine monophosphate), TDP (thymidine diphosphate), and TTP (thymidine triphosphate). The analogous nucleosides and nucleotides formed from thymine and ribose occur only very rarely in living systems; such is not the case with the other pyrimidines. The nucleotide derivatives of thymine do not exhibit as much activity as coenzymes , although TTP can readily donate one of its phosphate groups to adenosine diphosphate (ADP) to form adenosine triphosphate (ATP), an extremely important intermediate in the transfer of chemical energy in living systems. Since the thymine nucleotides contain only deoxyribose and not ribose, TTP is the source of thymidine only in deoxyribonucleic acid (DNA); there is no thymine in ribonucleic acid (RNA). Thymidine is significant because of its involvement in the biosynthesis of DNA and in the preservation and transfer of genetic information. See nucleic acid . |
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"thymine." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "thymine." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1E1-thymine.html "thymine." The Columbia Encyclopedia, 6th ed.. 2008. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-thymine.html |
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thymine
thy·mine / ˈ[unvoicedth]īˌmēn; -min/ • n. Biochem. a compound, C5H6N2O2, that is one of the four constituent bases of nucleic acids. A pyrimidine derivative, it is paired with adenine in double-stranded DNA. |
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"thymine." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "thymine." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O999-thymine.html "thymine." The Oxford Pocket Dictionary of Current English. 2009. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-thymine.html |
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thymine
thymine (th'y-meen) n. one of the nitrogen-containing bases (see pyrimidine) occurring in the nucleic acid DNA.
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"thymine." A Dictionary of Nursing. 2008. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "thymine." A Dictionary of Nursing. 2008. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O62-thymine.html "thymine." A Dictionary of Nursing. 2008. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O62-thymine.html |
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thymine
thymine A pyrimidine derivative and one of the major component bases of nucleotides and the nucleic acid DNA.
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"thymine." A Dictionary of Biology. 2004. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. "thymine." A Dictionary of Biology. 2004. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O6-thymine.html "thymine." A Dictionary of Biology. 2004. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O6-thymine.html |
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thymine
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MICHAEL ALLABY. "thymine." A Dictionary of Ecology. 2004. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "thymine." A Dictionary of Ecology. 2004. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O14-thymine.html MICHAEL ALLABY. "thymine." A Dictionary of Ecology. 2004. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O14-thymine.html |
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thymine
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MICHAEL ALLABY. "thymine." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "thymine." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O7-thymine.html MICHAEL ALLABY. "thymine." A Dictionary of Plant Sciences. 1998. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O7-thymine.html |
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thymine
thymine A pyrimidine base that occurs in DNA.
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MICHAEL ALLABY. "thymine." A Dictionary of Zoology. 1999. Encyclopedia.com. 10 Feb. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "thymine." A Dictionary of Zoology. 1999. Encyclopedia.com. (February 10, 2012). http://www.encyclopedia.com/doc/1O8-thymine.html MICHAEL ALLABY. "thymine." A Dictionary of Zoology. 1999. Retrieved February 10, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O8-thymine.html |
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