Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Science 4 April 2008:
Vol. 320. no. 5872, pp. 103 - 106
DOI: 10.1126/science.1152241
Prev | Table of Contents | Next

Reports

Reversible Compartmentalization of de Novo Purine Biosynthetic Complexes in Living Cells

Songon An,* Ravindra Kumar, Erin D. Sheets,* Stephen J. Benkovic*

Purines are synthesized de novo in 10 chemical steps that are catalyzed by six enzymes in eukaryotes. Studies in vitro have provided little evidence of anticipated protein-protein interactions that would enable substrate channeling and regulation of the metabolic flux. We applied fluorescence microscopy to HeLa cells and discovered that all six enzymes colocalize to form clusters in the cellular cytoplasm. The association and dissociation of these enzyme clusters can be regulated dynamically, by either changing the purine levels of or adding exogenous agents to the culture media. Collectively, the data provide strong evidence for the formation of a multi-enzyme complex, the "purinosome," to carry out de novo purine biosynthesis in cells.

Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, USA.

* To whom correspondence should be addressed. E-mail: sjb1{at}psu.edu (S.J.B.); eds11{at}psu.edu (E.D.S.); sua13{at}psu.edu (S.A.)

Read the Full Text


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
One-Carbon Metabolism-Genome Interactions in Folate-Associated Pathologies.
P. J. Stover (2009)
J. Nutr. 139, 2402-2405
   Abstract »    Full Text »    PDF »
An Internal Reaction Chamber in Dimethylglycine Oxidase Provides Efficient Protection from Exposure to Toxic Formaldehyde.
T. Tralau, P. Lafite, C. Levy, J. P. Combe, N. S. Scrutton, and D. Leys (2009)
J. Biol. Chem. 284, 17826-17834
   Abstract »    Full Text »    PDF »
Widespread reorganization of metabolic enzymes into reversible assemblies upon nutrient starvation.
R. Narayanaswamy, M. Levy, M. Tsechansky, G. M. Stovall, J. D. O'Connell, J. Mirrielees, A. D. Ellington, and E. M. Marcotte (2009)
PNAS 106, 10147-10152
   Abstract »    Full Text »    PDF »
Novel Activities of Glycolytic Enzymes in Bacillus subtilis: INTERACTIONS WITH ESSENTIAL PROTEINS INVOLVED IN mRNA PROCESSING.
F. M. Commichau, F. M. Rothe, C. Herzberg, E. Wagner, D. Hellwig, M. Lehnik-Habrink, E. Hammer, U. Volker, and J. Stulke (2009)
Mol. Cell. Proteomics 8, 1350-1360
   Abstract »    Full Text »    PDF »
Nicotinamide Mononucleotide Adenylyl Transferase-Mediated Axonal Protection Requires Enzymatic Activity But Not Increased Levels of Neuronal Nicotinamide Adenine Dinucleotide.
Y. Sasaki, B. P. S. Vohra, F. E. Lund, and J. Milbrandt (2009)
J. Neurosci. 29, 5525-5535
   Abstract »    Full Text »    PDF »


To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)