Inherent Regulation of EAL Domain-catalyzed Hydrolysis of Second Messenger Cyclic di-GMP

• DOI: 10.1074/jbc.m113.516195
• Publication Date: 2014-01-23T03:13:37Z
• Authors: Amit Sundriyal; Claudia Massa; Dietrich Samoray; Fabian Zehender; Timothy Sharpe; Urs Jenal; Tilman Schirmer
• Keywords: Second messenger system

The universal second messenger cyclic di-GMP (cdG) is involved in the regulation of a diverse range cellular processes bacteria. intracellular concentration dinucleotide determined by opposing actions diguanylate cyclases and cdG-specific phosphodiesterases (PDEs). Whereas most PDEs have accessory domains that are their activity, regulatory mechanism this class enzymes has remained unclear. Here, we use biophysical functional analyses to show isolated EAL domain PDE from Escherichia coli (YahA) fast thermodynamic monomer-dimer equilibrium, active only its dimeric state. Furthermore, our data indicate coupling between substrate binding dimerization with affinity being increased about 100-fold upon binding. Crystal structures YahA-EAL under various conditions (apo, Mg(2+), cdG·Ca(2+) complex) confirm structural dimer interface catalytic center. built-in properties probably facilitate modular, combination repertoire domains.