3c21
From Proteopedia
Structure of a bacterial DNA damage sensor protein with reaction product
Overview
To reveal mechanisms of DNA damage checkpoint initiation, we structurally and biochemically analyzed DisA, a protein that controls a Bacillus subtilis sporulation checkpoint in response to DNA double-strand breaks. We find that DisA forms a large octamer that consists of an array of an uncharacterized type of nucleotide-binding domain along with two DNA-binding regions related to the Holliday junction recognition protein RuvA. Remarkably, the nucleotide-binding domains possess diadenylate cyclase activity. The resulting cyclic diadenosine phosphate, c-di-AMP, is reminiscent but distinct from c-di-GMP, an emerging prokaryotic regulator of complex cellular processes. Diadenylate cyclase activity is unaffected by linear DNA or DNA ends but strongly suppressed by branched nucleic acids such as Holliday junctions. Our data indicate that DisA signals DNA structures that interfere with chromosome segregation via c-di-AMP. Identification of the diadenylate cyclase domain in other eubacterial and archaeal proteins implies a more general role for c-di-AMP in prokaryotes.
About this Structure
3C21 is a Single protein structure of sequence from Thermotoga maritima. Full crystallographic information is available from OCA.
Reference
Structural biochemistry of a bacterial checkpoint protein reveals diadenylate cyclase activity regulated by DNA recombination intermediates., Witte G, Hartung S, Buttner K, Hopfner KP, Mol Cell. 2008 Apr 25;30(2):167-78. PMID:18439896 Page seeded by OCA on Wed May 7 08:54:08 2008
