Nucleobase

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Nucleobase	Nucleoside
Image:Adenine chemical structure.png Adenine	Image:A chemical structure.png Adenosine A
Image:Guanine chemical structure.png Guanine	Image:G chemical structure.png Guanosine G
Image:Thymine chemical structure.png Thymine	Image:T chemical structure.png Thymidine T
Image:Uracil chemical structure.png Uracil	Image:U chemical structure.png Uridine U
Image:Cytosine chemical structure.png Cytosine	Image:C chemical structure.png Cytidine C
Image:Hypoxanthine chemical structure.svg Hypoxanthine	Image:HX chemical structure.svg Hypoxanthinosine HX
Image:Xanthine chemical structure.svg Xanthine	Image:X chemical structure.svg Xanthinosine X

Nucleobases are the parts of RNA and DNA that may be involved in pairing up (see also base pairs). These include cytosine, guanine, adenine, thymine (DNA), uracil (RNA) ans xanthine and hypoxanthine (mutated forms of guanine and, respectively, adenine). These are abbreviated as C, G, A, T, U, X and HX respectively. They are usually simply called bases in Genetics.

Uracil replaces thymine in RNA. These two bases are identical except that uracil lacks the 5' methyl group. Adenine and guanine belong to the double-ringed class of molecules called purines (abbreviated as R). Cytosine, thymine, and uracil are all pyrimidines (abbreviated as Y).

A base covalently bound to the 1' carbon of a ribose or deoxyribose is called a nucleoside, and a nucleoside with one or more phosphate groups attached at the 5' carbon is called a nucleotide.

1 Overall Information
2 Structure
3 See also
4 External links

[edit] Overall Information

Hypoxanthine and Xanthine are created through Mutagen presence, through De-amination (replacement of the Amine-Group with a Hydroxyl-Group). Hypoxanthine is produced from Adenine, Xanthin from Guanin and Uracil from Cytosin.

Because A, G, C and T appear in the DNA, these molecules are called DNA-bases; A, G, C and U are called respectively RNA-bases.

[edit] Structure

The "skeleton" of Adenine, Guanin, Hypoxanthine and Xanthine is Purine, hence the name Purin-bases.
The "skeleton" of Cytosin, Uracil and Thymin is Pyrimidine, hence Pyrimidine-bases.

[edit] See also

[edit] External links

Base pairing in DNA Double Helix (shows specific hydrogen bonds)

Nucleic acids and oligonucleotides edit
Nucleobases:	Adenine \| Thymine \| Uracil \| Guanine \| Cytosine \| Purine \| Pyrimidine
Nucleosides:	Adenosine \| Uridine \| Guanosine \| Cytidine \| Deoxyadenosine \| Thymidine \| Deoxyguanosine \| Deoxycytidine
Nucleotides:	AMP \| UMP \| GMP \| CMP \| ADP \| UDP \| GDP \| CDP \| ATP \| UTP \| GTP \| CTP \| cAMP \| cADPR \| cGMP
Deoxynucleotides:	dAMP \| TMP \| dGMP \| dCMP \| dADP \| TDP \| dGDP \| dCDP \| dATP \| TTP \| dGTP \| dCTP
Ribonucleic acids:	RNA \| mRNA \| tRNA \| rRNA \| ncRNA \| sgRNA \| shRNA \| siRNA \| snRNA \| miRNA \| snoRNA \| LNA
Deoxyribonucleic acids:	DNA \| mtDNA \| cDNA \| plasmid \| Cosmid \| BAC \| YAC \| HAC
Analogues of nucleic acids:	GNA \| PNA \| TNA\| morpholino
←Amino acids	Major families of biochemicals	Carbohydrates→