Cellular and Molecular Life Sciences

, Volume 65, Issue 23, pp 3699–3724

Structural biology of the purine biosynthetic pathway


DOI: 10.1007/s00018-008-8295-8

Cite this article as:
Zhang, Y., Morar, M. & Ealick, S.E. Cell. Mol. Life Sci. (2008) 65: 3699. doi:10.1007/s00018-008-8295-8


Purine biosynthesis requires ten enzymatic transformations to generate inosine monophosphate. PurF, PurD, PurL, PurM, PurC, and PurB are common to all pathways, while PurN or PurT, PurK/PurE-I or PurE-II, PurH or PurP, and PurJ or PurO catalyze the same steps in different organisms. X-ray crystal structures are available for all 15 purine biosynthetic enzymes, including 7 ATP-dependent enzymes, 2 amidotransferases and 2 tetrahydrofolate-dependent enzymes. Here we summarize the structures of the purine biosynthetic enzymes, discuss similarities and differences, and present arguments for pathway evolution. Four of the ATP-dependent enzymes belong to the ATP-grasp superfamily and 2 to the PurM superfamily. The amidotransferases are unrelated, with one utilizing an N-terminal nucleophileglutaminase and the other utilizing a triad glutaminase. Likewise the tetrahydrofolate-dependent enzymes are unrelated. Ancestral proteins may have included a broad specificity enzyme instead of PurD, PurT, PurK, PurC, and PurP, and a separate enzyme instead of PurM and PurL.


Purine biosynthesisprotein evolutionATP-grasp superfamilyPurM superfamilyamidotransferases

Copyright information

© Birkhäuser Verlag, Basel 2008

Authors and Affiliations

  1. 1.Department of Chemistry and Chemical Biology, Baker LaboratoryCornell UniversityIthacaUSA