Identification of c-di-GMP derivatives resistant to an EAL domain phosphodiesterase.

The bacterial second messenger signaling molecule bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP) controls important biological processes such as biofilm formation, virulence response, and motility. This second messenger is sensed by macromolecular targets inside the cell, both protein and RNA, which induce specific phenotypic responses critical for bacterial survival. One class of enzymes responsible for regulating the intracellular concentration of c-di-GMP, and therefore the physiological behavior of the cell, consists of the EAL domain phosphodiesterases, which degrade the second messenger to its linear form, pGpG.

The bacterial second messenger c-di-GMP: probing interactions with protein and RNA binding partners using cyclic dinucleotide analogs.

The ability of bacteria to adapt to a changing environment is essential for their survival. One mechanism used to facilitate behavioral adaptations is the second messenger signaling molecule bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP). c-di-GMP is widespread throughout the bacterial domain and plays a vital role in regulating the transition between the motile planktonic lifestyle and the sessile biofilm forming state.

Differential analogue binding by two classes of c-di-GMP riboswitches.

The ability of bacteria to adapt to a changing environment is essential for their survival. One mechanism bacteria have evolved to sense environmental cues and translate these signals into phenotypic changes uses the second messenger signaling molecule, cyclic diguanosine monophosphate (c-di-GMP). In addition to several classes of protein receptors, two classes of c-di-GMP-binding riboswitches (class I and class II) have been identified as downstream targets of the second messenger in this signaling pathway.

Structural basis of differential ligand recognition by two classes of bis-(3'-5')-cyclic dimeric guanosine monophosphate-binding riboswitches.

The bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP) signaling pathway regulates biofilm formation, virulence, and other processes in many bacterial species and is critical for their survival. Two classes of c-di-GMP-binding riboswitches have been discovered that bind this second messenger with high affinity and regulate diverse downstream genes, underscoring the importance of RNA receptors in this pathway. We have solved the structure of a c-di-GMP-II riboswitch, which reveals that the ligand is bound as part of a triplex formed with a pseudoknot.

Structural and biochemical determinants of ligand binding by the c-di-GMP riboswitch .

The bacterial second messenger c-di-GMP is used in many species to control essential processes that allow the organism to adapt to its environment. The c-di-GMP riboswitch (GEMM) is an important downstream target in this signaling pathway and alters gene expression in response to changing concentrations of c-di-GMP. The riboswitch selectively recognizes its second messenger ligand primarily through contacts with two critical nucleotides.