Gas-Phase Studies of Formamidopyrimidine Glycosylase (Fpg) Substrates.
Chemistry
; 22(11): 3881-90, 2016 Mar 07.
Article
em En
| MEDLINE
| ID: mdl-26894440
ABSTRACT
Gas-phase thermochemical properties (tautomerism, acidity, and proton affinity) have been measured and calculated for a series of nucleobase derivatives that have not heretofore been examined under vacuum. The studied species are substrates for the enzyme formamidopyrimidine glycosylase (Fpg), which cleaves damaged nucleobases from DNA. The gas-phase results are compared and contrasted to solution-phase data, to afford insight into the Fpg mechanism. Calculations are also used to probe the energetics of various possible mechanisms and to predict isotope effects that could potentially allow for discrimination between different mechanisms. Specifically, (18) O substitution at the ribose O4' is predicted to result in a normal kinetic isotope effect (KIE) for a ring-opening "endocyclic" mechanism and an inverse KIE for a direct base excision "exocyclic" pathway.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
DNA Glicosilases
/
DNA-Formamidopirimidina Glicosilase
/
Gases
Idioma:
En
Ano de publicação:
2016
Tipo de documento:
Article