A model for 3-methyladenine recognition by 3-methyladenine DNA glycosylase I (TAG) from Staphylococcus aureus.
Acta Crystallogr Sect F Struct Biol Cryst Commun
; 68(Pt 6): 610-5, 2012 Jun 01.
Article
em En
| MEDLINE
| ID: mdl-22684054
ABSTRACT
The removal of chemically damaged DNA bases such as 3-methyladenine (3-MeA) is an essential process in all living organisms and is catalyzed by the enzyme 3-MeA DNA glycosylase I. A key question is how the enzyme selectively recognizes the alkylated 3-MeA over the much more abundant adenine. The crystal structures of native and Y16F-mutant 3-MeA DNA glycosylase I from Staphylococcus aureus in complex with 3-MeA are reported to 1.8 and 2.2 Å resolution, respectively. Isothermal titration calorimetry shows that protonation of 3-MeA decreases its binding affinity, confirming previous fluorescence studies that show that charge-charge recognition is not critical for the selection of 3-MeA over adenine. It is hypothesized that the hydrogen-bonding pattern of Glu38 and Tyr16 of 3-MeA DNA glycosylase I with a particular tautomer unique to 3-MeA contributes to recognition and selection.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Staphylococcus aureus
/
Adenina
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DNA Glicosilases
Idioma:
En
Ano de publicação:
2012
Tipo de documento:
Article
País de afiliação:
Reino Unido