title: 3-Methyladenine-DNA glycosylase I from Escherichia coli-computer modeling and supporting experimental evidence.
abstract: TagA (3-methyladenine-DNA glycosylase I) excises 3-methyadenine and 3-methylguanine from alkylated DNA. The structure of this enzyme has not yet been determined experimentally. We propose a three-dimensional model of the TagA protein based on the threading algorithm. The model shows that TagA is a mostly alpha-helical protein, in agreement with circular dichroism measurements. None of the eight cysteines present in the TagA sequence forms a disulfide bridge in the model structure, which has also been experimentally verified with the use of Ellman method.
authors.affiliation: Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106 Warsaw, Poland.
authors.forename: D
authors.initials: D
authors.lastname: Plochocka
authors.forename: A
authors.initials: A
authors.lastname: Kierzek
authors.forename: T
authors.initials: T
authors.lastname: Obtulowicz
authors.forename: B
authors.initials: B
authors.lastname: Tudek
authors.forename: P
authors.initials: P
authors.lastname: Zielenkiewicz
mesh_terms: D000465:Algorithms; D000595:Amino Acid Sequence; D002942:Circular Dichroism; D003198:Computer Simulation; D003545:Cysteine / Q000737:chemistry; D045647:DNA Glycosylases; D004220:Disulfides / Q000737:chemistry; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009699:N-Glycosyl Hydrolases / Q000737:chemistry* / Q000235:genetics; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D017386:Sequence Homology, Amino Acid
chemical_list: D004220:Disulfides; C021565:3-methyladenine-DNA glycosylase; D045647:DNA Glycosylases; D009699:N-Glycosyl Hydrolases; D003545:Cysteine