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Found Cytosine 32 times.

Displaying results 1 to 10.

1. 5-hydroxymethylcytosine
A nucleotide base derived from cytosine which is used by the bacteriophage T4 in place of cytosine in its DNA . The substitution protects the bacteriophage from its own nuclease enzyme s (enzymes which cut apart DNA).

2. 5-methylcytosine (5MeC)
This is the methylated form of cytosine (a nitrogenous base in nucleic acids); i.e., a methyl group has been added to the cytosine molecule.

3. Apyrimidinic site
A site on DNA where a base is missing, in this case a pyrimidine (either cytosine or thymine ), but the phosphodiester backbone is still intact. Compare with apurinic site.

4. Arabinosylcytosine (araC)
An antibiotic which acts by blocking DNA synthesis. Its structure is derived from the pyrimidine cytosine by replacing the simple sugar ribose with the simple sugar arabinose .

5. AT content
The percentage of nitrogenous base s on a DNA molecule which are either adenine or thymine (from a possibility of four different ones, also including cytosine and guanine ). Also see GC content .

6. AT/GC ratio
The ratio of adenine - thymine base pair s to guanine - cytosine base pairs on a DNA molecule.

7. Base composition
In reference to nucleic acid, the proportion of the total bases consisting of guanine plus cytosine or thymine plus adenine base pairs. Usually expressed as a guanine + cytosine (G+C) value, e.g. 60% G+C.

8. Base pair (bp)
Two nitrogenous bases ( adenine and thymine or guanine and cytosine ) held together by weak bonds. Two strands of DNA are held together in the shape of a double helix by the bonds between base pairs.

9. Complementary base pairing
The pairing of complementary nucleotide base s ( adenine and thymine , guanine and cytosine ) to each other via hydrogen bond s from opposite strands of a double stranded nucleic acid (such as DNA or RNA ), thereby holding the double-stranded nucleic acid together.

10. Complementary nucleotides
The bonding preferences of nucleotides, Adenine with Thymine , and cytosine with Guanine . Also referred to as complementary base pairing.

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