2LBI

N2-dG:N2-dG interstrand cross-link induced by trans-4-hydroxynonenal

Summary for 2LBI

• Entry DOI: 10.2210/pdb2lbi/pdb
• NMR Information: BMRB: 17562
• Descriptor: DNA (5'-D(*GP*CP*TP*AP*GP*CP*GP*AP*GP*TP*CP*C)-3'), DNA (5'-D(*GP*GP*AP*CP*TP*CP*GP*CP*TP*AP*GP*C)-3'), (4S)-nonane-1,4-diol (3 entities in total)
• Functional Keywords: trans-4-hydroxynonenal, interstrand cross-link, dna
• Total number of polymer chains: 2
• Total formula weight: 7487.04

Authors

Huang, H.,Kozekov, I.D.,Wang, H.,Kozekova, A.,Rizzo, C.J.,Stone, M.P. (deposition date: 2011-03-31, release date: 2012-04-04, Last modification date: 2024-05-15)

Primary citation

Huang, H.,Wang, H.,Kozekova, A.,Rizzo, C.J.,Stone, M.P.
Formation of a N2-dG:N2-dG carbinolamine DNA cross-link by the trans-4-hydroxynonenal-derived (6S,8R,11S) 1,N2-dG adduct.
J.Am.Chem.Soc., 133:16101-16110, 2011

PubMed Abstract: Michael addition of trans-4-hydroxynonenal (HNE) to deoxyguanosine yields diastereomeric 1,N(2)-dG adducts in DNA. When placed opposite dC in the 5'-CpG-3' sequence, the (6S,8R,11S) diastereomer forms a N(2)-dG:N(2)-dG interstrand cross-link [Wang, H.; Kozekov, I. D.; Harris, T. M.; Rizzo, C. J. J. Am. Chem. Soc.2003, 125, 5687-5700]. We refined its structure in 5'-d(G(1)C(2)T(3)A(4)G(5)C(6)X(7)A(8)G(9)T(10)C(11)C(12))-3'·5'-d(G(13)G(14)A(15)C(16)T(17)C(18)Y(19)C(20)T(21)A(22)G(23)C(24))-3' [X(7) is the dG adjacent to the C6 carbon of the cross-link or the α-carbon of the (6S,8R,11S) 1,N(2)-dG adduct, and Y(19) is the dG adjacent to the C8 carbon of the cross-link or the γ-carbon of the HNE-derived (6S,8R,11S) 1,N(2)-dG adduct; the cross-link is in the 5'-CpG-3' sequence]. Introduction of (13)C at the C8 carbon of the cross-link revealed one (13)C8→H8 correlation, indicating that the cross-link existed predominantly as a carbinolamine linkage. The H8 proton exhibited NOEs to Y(19) H1', C(20) H1', and C(20) H4', orienting it toward the complementary strand, consistent with the (6S,8R,11S) configuration. An NOE was also observed between the HNE H11 proton and Y(19) H1', orienting the former toward the complementary strand. Imine and pyrimidopurinone linkages were excluded by observation of the Y(19)N(2)H and X(7) N1H protons, respectively. A strong H8→H11 NOE and no (3)J((13)C→H) coupling for the (13)C8-O-C11-H11 eliminated the tetrahydrofuran species derived from the (6S,8R,11S) 1,N(2)-dG adduct. The (6S,8R,11S) carbinolamine linkage and the HNE side chain were located in the minor groove. The X(7)N(2) and Y(19)N(2) atoms were in the gauche conformation with respect to the linkage, maintaining Watson-Crick hydrogen bonds at the cross-linked base pairs. A solvated molecular dynamics simulation indicated that the anti conformation of the hydroxyl group with respect to C6 of the tether minimized steric interaction and predicted hydrogen bonds involving O8H with C(20)O(2) of the 5'-neighbor base pair G(5)·C(20) and O11H with C(18)O(2) of X(7)·C(18). These may, in part, explain the stability of this cross-link and the stereochemical preference for the (6S,8R,11S) configuration.

PubMed: 21916419
DOI: 10.1021/ja205145q

Experimental method

SOLUTION NMR