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1.1: Nitrogenous bases, Nucleosides and Nucleotides

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    100582
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    Play with the adenine molecule above, you can rotate it and zoom in and out!

    Nucleotide structure review

    Recall some basic structural features of the nucleotide building blocks of DNA. A nucleotide is composed of a nitrogenous base, deoxyribose (five-carbon sugar), and at least one phosphate group. The nitrogenous bases are purines such as adenine (A) and guanine (G), or pyrimidines such as cytosine (C), thymine (T), and uracil (U).

    70945f0a6632ee3417afffceb741d5c1c8d468d0-770x762.jpg

    Figure 1.

    Each nucleotide is made up of a sugar (ribose for nucleotides in RNA, deoxyribose for nucleotides in DNA), a phosphate group, and a nitrogenous base. The purines have a double ring structure with a six-membered ring fused to a five-membered ring. Pyrimidines are smaller with a single six-membered ring structure. The carbon atoms of the five-carbon sugar are numbered 1', 2', 3', 4', and 5' (1' is read as “one prime”).

    Naming Nucleobases, Nucleosides and Nucleotides

    Nucleic Acid Base (Nucleobase) Nucleoside Nucleotide (Given for a nucleoside-5'-monophosphate)
    RNA Adenine (A) Adenosine Adenosine-5'-monophosphate or adenylate (AMP)
    Cytosine (C) Cytidine Cytidine-5'-monophosphate or cytidylate (CMP)

    Guanine (G)

    Guanosine Guanosine-5'-monophosphate or guanylate (GMP)
    Uracil (U) Uridine Uridine-5'-monophosphate or uridylate (UMP)
    Nucleic Acid Base (Nucleobase) Nucleoside Nucleotide (Given for a deoxynucleoside-5'-monophosphate)
    DNA Adenine (A)

    Deoxyadenosine

    Deoxyadenosine-5'-monophosphate or deoxyadenylate (dAMP)

    Cytosine (C) Deoxycytidine Deoxycytidine-5'-monophosphate or deoxycytidylate (dCMP)
    Guanine (G) Deoxyguanosine Deoxyguanosine-5'-monophosphate or deoxyguanylate (dGMP)
    Thymine (T) Deoxythymidine

    Deoxythymidine-5'-monophosphate or thymidylate (dTMP)

    [Because the ribonucleotide version is so rare people often call deoxythymidine just thymidine and deoxythymidylate just thymidylate]




    1.1: Nitrogenous bases, Nucleosides and Nucleotides is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by LibreTexts.

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