Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2007-12-6
pubmed:abstractText
FapydG is a common oxidative DNA lesion involving opening of the imidazole ring. It shares the same precursor as 8-oxodG and can be excised by the same enzymes as 8-oxodG. However, the loss of the aromatic imidazole in FapydG results in a reduction of the double bond character between C5 and N7, with an accompanying increase in conformational flexibility. Experimental characterization of FapydG is hampered by high reactivity, and thus it is desirable to investigate structural details through computer simulation. We show that the existing Amber force field parameters for FapydG do not reproduce X-ray structural data. We employed quantum mechanics energy profile calculations to derive new molecular mechanics parameters for the rotation of the dihedral angles in the eximidazole moiety. Using these parameters, all-atom simulations in explicit water reproduce the nonplanar conformation of cFapydG in the crystal structure of the complex with L. lactis glycosylase Fpg. We note that the nonplanar structure is stabilized by an acidic residue that is not present in most Fpg sequences. Simulations of the E-->S mutant, as present in E. coli, resulted in a more planar conformation, suggesting that the highly nonplanar form observed in the crystal structure may not have direct biological relevance for FapydG.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0192-8651
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
29
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
17-23
pubmed:dateRevised
2009-2-5
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Molecular mechanics parameters for the FapydG DNA lesion.
pubmed:affiliation
Department of Chemistry, Stony Brook University, Stony Brook, NY 11794-3400, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural