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PleD

Overview

spinqualitylabelsall models Diguanylate cyclase PleD 1w25 Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

from Caulobacter crescentus is a response regulator with an unorthodox catalytic, diguanylate cyclase, output domain. It is composed of a canonical CheY-like response regulator receiver (, also called D1) domain, a Rec-like (, also called D2) adaptor domain, and a C-terminal domain that confers the catalytic acitvity.

The GGDEF domain is named after the highly conserved (in PleD it is GGEEF) that locates to a β-hairpin.

Substrate binding

spinqualitylabelsall models Diguanylate cyclase PleD 2v0n Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

The motif is part of the as identified in the structure of PleD in complex with . The GGDEF domain binds only one GTP substrate molecule. For the reaction to proceed, two GTP loaded GGDEF domains have to align antiparallely.

Complete active site

Theoretical Model: The protein structure described on this page was determined theoretically, and hence should be interpreted with caution.

After binding of the (here we show GMP, please update), it is believed that two GGDEF domains associate antiparallely to form a catalytically competent dimer (, ). Then, by inter-molecular nucleophilic in-line attack of the O3' atom onto the α-phosphorous of the other GTP substrate molecule, two phosphodiester bonds are formed under release of two pyrophosphate molecules (2 GTP -> c-di-GMP + 2 PPi).