title: Ab initio molecular orbital evaluation of the hydrogen bond energy of base pairs formed between substituted 1-methylcytosine derivatives and 9-methylguanine.
abstract: The substitution effect on hydrogen bond energy of the Watson-Crick type base pair between 9-methylguanine (G) and chemically modified 1-methylcytosine (CX) derivatives was evaluated by ab initio molecular orbital theory. A remarkable trend was observed in the substitution effect of the hydrogen bond stability: Cytosine derivatives possessing an electron-donating group form stable base pairs with guanine. However, both the hydrogen bond distance and the charge distribution were not good indexes for the hydrogen bond status in CX-G base pairing.
authors.affiliation: National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8565, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Kawahara
authors.forename: A
authors.initials: A
authors.lastname: Kobori
authors.forename: K
authors.initials: K
authors.lastname: Taira
authors.forename: M
authors.initials: M
authors.lastname: Sekine
authors.forename: T
authors.initials: T
authors.lastname: Uchimaru
mesh_terms: D020029:Base Pairing; D003596:Cytosine / Q000031:analogs & derivatives* / Q000737:chemistry*; D006147:Guanine / Q000031:analogs & derivatives* / Q000737:chemistry*; D006860:Hydrogen Bonding
chemical_list: C031532:1-methylcytosine; C116701:9-methylguanine; D006147:Guanine; D003596:Cytosine