The mechanism of the glycosylase reaction with hOGG1 base-excision repair enzyme: concerted effect of Lys249 and Asp268 during excision of 8-oxoguanine

0475942 - ÚOCHB 2018 RIV GB eng J - Článek v odborném periodiku
Šebera, Jakub - Hattori, Y. - Sato, D. - Řeha, David - Nencka, Radim - Kohno, T. - Kojima, C. - Tanaka, Y. - Sychrovský, Vladimír
The mechanism of the glycosylase reaction with hOGG1 base-excision repair enzyme: concerted effect of Lys249 and Asp268 during excision of 8-oxoguanine.
Nucleic Acids Research. Roč. 45, č. 9 (2017), s. 5231-5242. ISSN 0305-1048. E-ISSN 1362-4962
Grant CEP: GA ČR GA13-27676S
Institucionální podpora: RVO:61388963 ; RVO:61388971
Klíčová slova: 8-oxoguanine * hOGG1 * QM/MM * NMR * base-excision repair
Obor OECD: Physical chemistry
Impakt faktor: 11.561, rok: 2017
https://academic.oup.com/nar/article-lookup/doi/10.1093/nar/gkx157

The excision of 8-oxoguanine (oxoG) by the human 8-oxoguanine DNA glycosylase 1 (hOGG1) base-excision repair enzyme was studied by using the QM/MM (M06-2X/6-31G(d,p): OPLS2005) calculation method and nuclear magnetic resonance (NMR) spectroscopy. The calculated glycosylase reaction included excision of the oxoG base, formation of Lys249-ribose enzyme-substrate covalent adduct and formation of a Schiff base. The formation of a Schiff base with Delta G(#) = 17.7 kcal/mol was the rate-limiting step of the reaction. The excision of the oxoG base with Delta G(#) = 16.1 kcal/mol proceeded via substitution of the C1'-N9 N-glycosidic bond with an H-N9 bond where the negative charge on the oxoG base and the positive charge on the ribose were compensated in a concerted manner by NH3+(Lys249) and CO2- (Asp268), respectively. The effect of Asp268 on the oxoG excision was demonstrated with H-1 NMR for WT hOGG1 and the hOGG1(D268N) mutant: the excision of oxoG was notably suppressed when Asp268 was mutated to Asn. The loss of the base-excision function was rationalized with QM/MM calculations and Asp268 was confirmed as the electrostatic stabilizer of ribose oxocarbenium through the initial base-excision step of DNA repair. The NMR experiments and QM/MM calculations consistently illustrated the base-excision reaction operated by hOGG1.
Trvalý link: http://hdl.handle.net/11104/0272532