Naturallyoccurring red-light activated diguanylyl cyclases (PadC) are constituted of acanonical bacteriophytochrome , able to photointerconvert between aninactive state (Pr) and an active conformation (Pfr) by red- light illuminationleading to isomerization of its biliverdin chromophore. The photosensory moduleis fused to a GGDEF domain  featuring diguanylyl cyclase activity, which is involvedin synthesis of the bacterial second messenger bis-(3′-5′) cyclic-dimeric-GMP.
Using biochemicaland biophysical methods we obtained structural details of a full-length PadC inthe Pr-state that supports the involvement of previously proposed importantstructural elements of phytochrome signaling . Moreover, we highlight theimportance of the sensor-effector linker element and show that its composition isfine-tuned for enabling the conformational dynamics required for signaltransduction. Currently we are addressing structural details of the Pfr state toimprove our understanding of molecular mechanisms involved in communication betweenthe phytochrome, the sensor-effector linker and the functional output domain.
Acknowledgements:This project has been initiated with a startup financing grant by GrazUniversity of Technology (F-AF5-648-01). A.W. acknowledges funding by theAustrian Science fund (FWF): P27124. G.G. and S.E. are supported by theAustrian Science Fund through the PhD programme “DK Molecular Enzymology”(W901).
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|Publication status||Published - 27 Jun 2016|
|Event||FEBS Advanced Methods in Macromolecular Crystallization VII - Nové Hrady, Czech Republic|
Duration: 27 Jun 2016 → 2 Jul 2016
|Conference||FEBS Advanced Methods in Macromolecular Crystallization VII|
|Period||27/06/16 → 2/07/16|
- Structural biology
Fields of Expertise
- Human- & Biotechnology