1k5f
From Proteopedia
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SOLUTION STRUCTURE OF THE S-STYRENE ADDUCT IN THE RAS61 SEQUENCE
Overview
Conformations of (R)-beta-(N(6)-adenyl)styrene oxide and, (S)-beta-(N(6)-adenyl)styrene oxide adducts at position X(6) in, d(CGGACXAGAAG).d(CTTCTTGTCCG), incorporating codons 60, 61 (underlined), and 62 of the human N-ras protooncogene, were refined from (1)H NMR data., These were designated as the beta-R(61,2) and beta-S(61,2) adducts. A, total of 533 distance restraints and 162 dihedral restraints were used for, the molecular dynamics calculations of the beta-S(61,2) adduct, while 518, distances and 163 dihedrals were used for the beta-R(61,2) adduct. The, increased tether length of the beta-adducts results in two significant, changes in adduct structure as compared to the corresponding, alpha-styrenyl adducts [Stone, M. P., and Feng, B. (1996) Magn. Reson., Chem. 34, S105-S114]. First, it reduces the distortion introduced into the, DNA duplex. For both the beta-R(61,2) and beta-S(61,2) adducts, the, styrenyl moiety was positioned in the major groove of the duplex with, little steric hindrance. Second, it mutes the influence of stereochemistry, at the alpha-carbon such that both the beta-R(61,2) and beta-S(61,2), adducts exhibit similar conformations. The results were correlated with, site-specific mutagenesis experiments that revealed the beta-R(61,2) and, beta-S(61,2) adducts were not mutagenic and did not block polymerase, bypass.
About this Structure
1K5F is a Protein complex structure of sequences from [1]. Full crystallographic information is available from OCA.
Reference
The nonmutagenic (R)- and (S)-beta-(N(6)-adenyl)styrene oxide adducts are oriented in the major groove and show little perturbation to DNA structure., Hennard C, Finneman J, Harris CM, Harris TM, Stone MP, Biochemistry. 2001 Aug 21;40(33):9780-91. PMID:11502171
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