3bvs

Publication Abstract from PubMed

DNA glycosylases safeguard the genome by locating and excising chemically modified bases from DNA. AlkD is a recently discovered bacterial DNA glycosylase that removes positively charged methylpurines from DNA, and was predicted to adopt a protein fold distinct from from those of other DNA repair proteins. The crystal structure of Bacillus cereus AlkD presented here shows that the protein is composed exclusively of helical HEAT-like repeats, which form a solenoid perfectly shaped to accommodate a DNA duplex on the concave surface. Structural analysis of the variant HEAT repeats in AlkD provides a rationale for how this protein scaffolding motif has been modified to bind DNA. We report 7mG excision and DNA binding activities of AlkD mutants, along with a comparison of alkylpurine DNA glycosylase structures. Together, these data provide important insight into the requirements for alkylation repair within DNA and suggest that AlkD utilizes a novel strategy to manipulate DNA in its search for alkylpurine bases.

A new protein architecture for processing alkylation damaged DNA: the crystal structure of DNA glycosylase AlkD.,Rubinson EH, Metz AH, O'Quin J, Eichman BF J Mol Biol. 2008 Aug 1;381(1):13-23. Epub 2008 Jun 5. PMID:18585735^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.