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Updated: Jul 13, 2026
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Imaging G-protein Coupled Receptor (GPCR)-mediated Signaling Events that Control Chemotaxis of Dictyostelium Discoideum
Published on: September 20, 2011
Activation of the diguanylate cyclase PleD by phosphorylation-mediated dimerization
Ralf Paul1, Sören Abel, Paul Wassmann
1Biozentrum, University of Basel, Klingelbergstrasse 70, Basel CH-4056, Switzerland.
The Journal of Biological Chemistry
|July 21, 2007
Summary
Bacterial diguanylate cyclases (DGCs) require dimerization for activity. This study shows PleD dimerization is essential for cyclic di-GMP synthesis and cellular localization in Caulobacter crescentus.
Area of Science:
- Bacterial signaling
- Enzymology
- Molecular biology
Background:
- Diguanylate cyclases (DGCs) synthesize cyclic di-GMP, a crucial bacterial second messenger.
- The catalytic and regulatory mechanisms of DGCs, including the role of oligomerization, are not fully understood.
- PleD, a Caulobacter crescentus DGC, is activated by phosphorylation, but its structural changes remain unclear.
Purpose of the Study:
- To investigate the role of oligomerization in PleD's catalytic activity and regulation.
- To elucidate the structural changes associated with PleD activation.
- To understand the spatial control of PleD activity within the cell.
Main Methods:
- In vitro and in vivo analysis of PleD.
- Activation of PleD using beryllium fluoride.
- Cross-linking and fractionation experiments.
- Analysis of PleD localization in Caulobacter crescentus.
Main Results:
- PleD activation by beryllium fluoride induces dimerization and cyclic di-GMP synthesis.
- DGC activity is exclusively found in the PleD dimer fraction.
- Product inhibition is independent of PleD activation status.
- Dimerization mediates PleD localization to the differentiating cell pole.
Conclusions:
- Dimerization is essential for PleD catalytic activity.
- Oligomerization represents a key regulatory mechanism for DGCs.
- Protein dimerization controls both enzymatic function and subcellular localization, linking activation to spatial regulation.
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