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Home > A. Molecular pathology > hypoxanthine


Wednesday 24 September 2008

Hypoxanthine is a naturally occurring purine derivative. It is occasionally found as a constituent of nucleic acids where it is present in the anticodon of tRNA in the form of its nucleoside inosine. It is also known as 6-Hydroxypurine.

Hypoxanthine is a necessary additive in certain cell, bacteria and parasite cultures as a substrate and nitrogen source. For example it is commonly a required reagent in malaria parasite cultures since Plasmodium falciparum requires a source of hypoxanthine for nucleic acid synthesis and energy metabolism.


Hypoxanthine is one of the products of the action of xanthine oxidase on xanthine, though more normally in purine degradation, hypoxanthine is formed from oxidation of xanthine by xanthine oxidase.

Hypoxanthine-guanine phosphoribosyltransferase converts hypoxanthine into inosinic acid or inosine monophosphate (IMP) in nucleotide salvage.

Hypoxanthine is also a spontaneous deamination product of adenine. Because of its resemblance to guanine, the spontaneous deamination of adenine can lead to an error in DNA transcription/replication.