NMR-Based Solution Structure of Escherichia coli Base Excision Repair Protein Formamidopyrimidine-DNA Glycosylase
EMSL Project ID
2150
Abstract
Introduction. Cellular DNA is ceaselessly exposed to endogenous agents, such as the reactive free radicals produced during oxidative metabolism, and exogenous agents, such as ionizing radiation, that damage the DNA. Unrepaired, oxidative DNA lesions may have deleterious cellular consequences, including cell death, mutagenesis, carcinogenesis, and aging. A number of repair pathways have evolved to prevent biological expression of oxidative DNA damage. One mechanism, base excision repair (BER), appears to be responsible for the replacement of most oxidative base damage. Formamidopyrimidine-DNA glycosylase is a key BER enzyme in prokaryotes. Substrates recognized and released by the DNA glycosylase activity of Fpg include 7,8-dihydro-8-oxoguanosine(8OG), 2,6-diamino-4-hydroxy-5-formamido pyrimidine, the adenine equivalents, triaminooxazolone, 5-hydroxyuracil, 5-hydroxycytosine, 5,6-dihydrothymine, and a-R-hydroxy-b-ureidoisobutiric acid. In vitro, Fpg binds double-stranded DNA and performs three catalytic activites: it is a (i) DNA glycosylase, (ii) apurinic/apyrimidinic lyase, and (iii) deoxyribophosphodiesterase. Our requests for time on the 800 MHz (1H) spectrometer is to conduct NMR experiments aimed at determining the solution structure of Fpg from Escherichia coli and studying the structural basis for the biologically activities of Fpg. The primary need for collecting data on such a high field instruments is the size of Fpg, it is a 269-residue protein with a molecular weight of 30.2 kDa. NOTE: Complete proposal is provided as hard-copy.
Project Details
Project type
Capability Research
Start Date
2001-03-28
End Date
2001-05-22
Status
Closed
Released Data Link
Team
Principal Investigator