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Protein Domain : IPR012226

Name  Oxygen sensor diguanylate cyclase/c-di-GMP phosphodiesterase Short Name  Dos
Type  Family Description  Members of this group are signal transduction proteins that are direct oxygen sensors and are involved in regulation of cellular processes via the effector molecule cyclic diguanylate (c-di-GMP, bis(3',5')-cyclic diguanylic acid). They contain PAS/PAC, GGDEF, and EAL domains and have diguanylate cyclase and phosphodiesterase activities. Related groups with similar domain architectures contain different versions of PAS/PAC domain, and are thought to have different, often not yet determined biological functions (e.g., , amongst others).Escherichia coliDos (YddU) and Acetobacter xylinum (Gluconacetobacter xylinus) PdeA1 proteins have been shown to be direct, haem-based oxygen sensors [, , ]. Their N-terminal PAS domains are responsible for haem-binding [, ]. PAS/PAC is a ubiquitous intracellular sensory domain. It is located in the cytoplasm and sense changes in redox potential in the electron transport system or overall cellular redox status. PAS domains can monitor changes in light, oxygen or small ligands in a cell, and sense environmental factors that cross the cell membrane and/or affect cell metabolism [, , ]. In the haem-containing subgroup of PAS domains, the haem pocket acts as a ligand-specific trap []. The ligand binding to a haem-containing PAS domain leads to either activation or inhibition of a regulated (catalytic) domain (here, GGDEF and/or EAL domains). Phosphodiesterase activity with cAMP of E. coli Dos has been shown to be regulated by the haem redox state []. Similarly, Acetobacter xylinum PdeA1 is regulated by reversible binding of O2to the haem [].The catalytic function of the members of this group has also been experimentally determined.Cyclic di-GMP (c-di-GMP) is the specific nucleotide regulator of beta-1,4-glucan (cellulose) synthase in Acetobacter xylinum []. In a study of the regulation of biosynthesis of extracellular cellulose in Acetobacter xylinum [], the search for the enzymes that synthesise and hydrolyse cyclic di-GMP resulted in the identification of six proteins with identical domain architecture containing PAS, GGDEF and EAL domains. Three of them exhibited diguanylate cyclase activity (Dgc1-3), and three others - phosphodiesterase activity (PdeA1-3) [, ]. Likewise, E. coli Dos has been shown to have phosphodiesterase activity [].Genetic complementation using genes from three different bacteria encoding proteins with GGDEF domains as the only element in common indicate that the GGDEF domain is responsible for the diguanylate cyclase activity of these proteins []. Even prior to these results, the notion that the GGDEF domain is a diguanylate cyclase was supported by the detailed analysis of its sequence, which shows conservation of the proposed nucleotide-binding loop in alignment with eukaryotic adenylate cyclases []. By exclusion, the EAL domain emerged as the best candidate for the role of c-di-GMP phosphodiesterase. Indeed, the sequence of this domain contains several conserved aspartates, which could participate in metal binding and form a phosphodiesterase active site []. It is not clear what differences make one subgroup of these proteins to act as phosphodiesterases, and another - as diguanylate cyclases, while containing both domains.PAS, GGDEF and EAL domains are found in many other signal transduction proteins with various domain architectures (e.g., , , , , and many others).For additional information please see [, ].

Publication Counts Displayer

0 Child Features

6 Contains

DB identifier Name Short Name Type
IPR000014 PAS domain PAS Domain
IPR003018 GAF domain GAF Domain
IPR013767 PAS fold PAS_fold Domain
IPR001633 Diguanylate phosphodiesterase, EAL domain Diguanylate_PEstase_EAL_dom Domain
IPR013656 PAS fold-4 PAS_4 Domain
IPR000160 GGDEF domain GGDEF_dom Domain

1 Cross References

Source . Name

Subject . Primary Identifier
PIRSF005925 PIRSF IPR012226

1 Data Sets

Name URL
InterPro data set  

0 Found In

0 GO Annotation

0 Ontology Annotations

0 Parent Features

0 Proteins