guanineZoomA-Z

Subject - Biochemistry

Guanine is the trivial name for 2-amino-1,9-dihydropurin-6-one.

It has the molecular formula C5H5N5O. and a molecular mass of ($Mr$) of 151.13 $Da$.

Fig.1
Structural formula of guanine

Besides , guanine belongs to the purine bases of nucleotides. Guanine is formed biosynthetically in organisms from basic building blocks, via different recycling pathways from purine derivatives or by acidic hydrolysis of the nucleoside guanosine. It ocurs as base in DNA as well as in RNA. Additionally, guanosine triphosphate GTP is an important supplier of energy in muscles and in the biosynthesis of proteins.

In DNA and RNA, guanine binds to the pyrimidine base cytosine through three hydrogen bonds. In addition, it can bind in RNA to by forming two hydrogen bonds without destroying the geometry of the polynucleotide.

The derivatives 8-azaguanine and 6-thioguanine shows antineoplastic activity.