Polymorphism of the signaling molecule c-di-GMP.

ABSTRACT: Using UV, CD, and NMR, we demonstrate that the important bacterial signaling molecule involved in biofilm formation, cyclic diguanosine monophosphate (c-di-GMP), exists as a mixture of five different but related structures in an equilibrium that is sensitive both to its concentration and to the metal present. At the lower concentrations used for UV and CD work (0.05-0.5 mM), Li(+), Na(+), Cs(+), and Mg(2+) favor a bimolecular self-intercalated structure, while K(+), Rb(+), and NH(4)(+) favor formation of one or more guanine quartet complexes as well. At the higher NMR concentrations ( approximately 30 mM), the bimolecular structures associate and rearrange to a mixture of all-syn and all-anti tetramolecular and octamolecular quartet complexes. With K(+) the octamolecular complexes predomin

SUBMITTER: Zhang Z 

PROVIDER: S-EPMC2535936 | biostudies-literature | 2006 May

REPOSITORIES: biostudies-literature