Biology:Diadenylate cyclase

From HandWiki
Short description: DNA binding protein
diadenylate cyclase
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Diadenylate cyclase homooctamer, Thermotoga maritima
Identifiers
EC number2.7.7.85
Databases
IntEnzIntEnz view
BRENDABRENDA entry
ExPASyNiceZyme view
KEGGKEGG entry
MetaCycmetabolic pathway
PRIAMprofile
PDB structuresRCSB PDB PDBe PDBsum

Diadenylate cyclase EC 2.7.7.85, DNA integrity scanning protein DisA is a DNA binding protein[1] participates in a DNA-damage check-point. DisA forms globular foci that rapidly scan along the chromosomes searching for lesions. Catalytic activity

2 ATP [math]\displaystyle{ \rightleftharpoons }[/math] 2 diphosphate + cyclic di-3',5'-adenylate.

This enzyme has diadenylate cyclase activity, catalyzing the condensation of 2 ATP molecules into cyclic di-AMP (c-di-AMP). c-di-AMP likely acts as a signaling molecule that may couple DNA integrity with a cellular process. This rate-limiting step is the accessibility of the active site; mutating the possible exit tunnel (residues 128-130) increases product 2-fold despite Arg-130 being important for ATP-binding. Does not convert GTP to c-di-GMP.

References

  1. "Structural biochemistry of a bacterial checkpoint protein reveals diadenylate cyclase activity regulated by DNA recombination intermediates". Molecular Cell 30 (2): 167–78. April 2008. doi:10.1016/j.molcel.2008.02.020. PMID 18439896.