DNA contains four different nitrogenous bases&colon; adenine, guanine, cytosine and thymine. RNA also contains adenine, guanine, and cytosine, but replaces thymine with uracil. The most common nitrogenous bases are adenine, cytosine, guanine, thymine, and uracil. It consists of 4 nucleotides guanine, thymine, cytosine, and adenine. It can cause deamination of the amino groups of Adenine, Guanine and Cytosine. The guanine nucleoside is called guanosine. Purine metabolism involves the formation of adenine and guanine. The three others are guanine, cytosine and thymine. The others are adenine, guanine, and cytosine. This normally consists of 7MeGpppN where N is normally adenine or guanine. Actinobacteria have high guanine and cytosine content in their DNA. They include the nucleobases adenine (2) and guanine (3). Family 2 excise uracil from mismatches with guanine. It is rich in guanine and cytosine content. The A is alanine146, which provides specificity for guanine rather than adenine.