The formation of mispairs by 8‐oxyguanine as a pathway of mutations induced by irradiation and oxygen radicals

Poltev, V. I.; Shulyupina, N. V.; Брусков, В. И.

doi:10.1002/jmr.300030105

Cited by 13 publications

(11 citation statements)

References 18 publications

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“…1B, the L-oriented construct measures the sum of (T⅐G) lagging ϩ (A⅐C) leading , whereas the R-oriented construct measures (T⅐G) leading ϩ (A⅐C) lagging . Given that T⅐G mispairs are generally much more frequent than A⅐C mispairs (30)(31)(32)(33)(34)(35)(36)(37), the L orientation measures (T⅐G) lagging , and the R orientation measures (T⅐G) leading . Our observation that the R orientation is more mutable than the L orientation (Tables 2 and 3) thus indicates that the leading strand produces more T⅐G errors and therefore that lagging strand replication is the more accurate one.…”

Section: Discussionmentioning

confidence: 99%

“…In deciding which mispair may be predominantly responsible for each base pair substitution, we surveyed the literature for direct measurements of misinsertion frequencies as well as the relative efficiencies by which the various mispairs can be extended by DNA polymerases (30)(31)(32)(33)(34)(35)(36)(37). The latter aspect is important because reduced extension efficiency correlates with increased removal by exonucleolytic proofreading (e.g., see ref.…”

Section: Discussionmentioning

confidence: 99%

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Unequal fidelity of leading strand and lagging strand DNA replication on the Escherichia coli chromosome

Fijałkowska

Jonczyk

Tkaczyk

et al. 1998

Proc. Natl. Acad. Sci. U.S.A.

156

188

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We have investigated the question whether during chromosomal DNA replication in Escherichia coli the two DNA strands may be replicated with differential accuracy. This possibility of differential replication fidelity arises from the distinct modes of replication in the two strands, one strand (the leading strand) being synthesized continuously, the other (the lagging strand) discontinuously in the form of short Okazaki fragments. We have constructed a series of lacZ strains in which the lac operon is inserted into the bacterial chromosome in the two possible orientations with regard to the chromosomal replication origin oriC. Measurement of lac reversion frequencies for the two orientations, under conditions in which mutations ref lect replication errors, revealed distinct differences in mutability between the two orientations. As gene inversion causes a switching of leading and lagging strands, these findings indicate that leading and lagging strand replication have differential fidelity. Analysis of the possible mispairs underlying each specific base pair substitution suggests that the lagging strand replication on the E. coli chromosome may be more accurate than leading strand replication.The question as to how organisms duplicate their DNA with high accuracy is of fundamental interest. Previous studies have revealed the functioning of at least three separate steps, base selection, proofreading, and DNA mismatch repair, which, by their sequential action, are responsible for the low error rate of Ϸ10 Ϫ10 per base replicated (1, 2). The most detailed information about this process is available for the bacterium E. coli based on both enzymological and genetical data. Replication of the E. coli chromosome is performed by DNA polymerase III holoenzyme, an asymmetric dimeric enzyme composed of 18 subunits (10 distinct) that simultaneously replicates the leading and lagging strand of the replication fork (for review, see ref.3). It contains two polymerase core units, one for each strand, each consisting of three tightly associated subunits, ␣, , and . Of these, ␣ is the polymerase (dnaE gene product), (dnaQ gene product) is a 3Ј 3 5Ј exonuclease that performs an editing function, and is a small subunit of unknown function. Additional components of the holoenzyme include the subunit ( 2 ) that dimerizes the two cores, the ␤ subunit (␤ 2 ) that encircles the DNA and tethers each DNA polymerase to the DNA to ensure high processivity, and the five-subunit ␥ complex (␥, ␦, ␦Ј, , and ) that loads the ␤ rings onto the DNA.With regard to the fidelity of polymerase III holoenzyme, as studied both in vivo and in vitro, the main focus has been on the role of the ␣ and subunits. The ␣ (polymerase) subunit plays a critical role through the process of base selection, selecting with great preference correct nucleotides at the nucleotide insertion step. The subunit, in conjunction with the polymerase, is responsible for the subsequent proofreading step, in which by virtue of its 3Ј exonuclease activity incorrectly inserted ...

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Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Unequal fidelity of leading strand and lagging strand DNA replication on the Escherichia coli chromosome

Fijałkowska

Jonczyk

Tkaczyk

et al. 1998

Proc. Natl. Acad. Sci. U.S.A.

156

188

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“…In 1980's it was shown that the physical properties, conformations and the biological functions in many respects are determined by the non-bonded interactions [109]. The non-bonded interactions were calculated using atom-atom potential functions having the form:…”

Section: Insert Figure 1 Herementioning

confidence: 99%

“…The atomic charges used in formulas (2) and (3) were obtained by quantum chemistry methods. The effective charges on atoms the authors [109,110] have received by summation of the π-electron charges, determined by the Hückel method [110], and σ-electron charges, calculated with help of parameter suggested by Berthod and Pullman [111]. By using these new non-bonded atom-atom potentials for calculating the non-bonded interactions, important and new results were obtained.…”

Section: Insert Figure 1 Herementioning

confidence: 99%

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Role of quantum chemical calculations in molecular biophysics with a historical perspective

Kukushkin

Jalkanen

2009

Theor Chem Acc

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We discuss how the basic principles of quantum chemistry and quantum mechanics can be and have been applied to a variety of problems in molecular biophysics. First, the historical development of quantum concepts in biophysics is discussed. Next, we describe a series of interesting applications of quantum chemical methods for studying biologically active molecules, molecular structures and some of the important processes which play a role in living organisms. We discuss the application of quantum chemistry to such processes as energy storage and transformation, and the transmission of genetic information. Quantum chemical approaches are essential to comprehend and understand the molecular nature of these processes. To conclude our work, we present a short discussion of the perspectives of quantum chemical methods in modern biophysics, the field of experimental and theoretical chiral vibrational and electronic spectroscopy.

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UV Radiation, DNA Damage, Mutations and Skin Cancer

Gruijl

2006

Nato Science Series: IV: Earth and Environmental Sciences

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The formation of mispairs by 8‐oxyguanine as a pathway of mutations induced by irradiation and oxygen radicals

Cited by 13 publications

References 18 publications

Unequal fidelity of leading strand and lagging strand DNA replication on the Escherichia coli chromosome

Unequal fidelity of leading strand and lagging strand DNA replication on the Escherichia coli chromosome

Role of quantum chemical calculations in molecular biophysics with a historical perspective

UV Radiation, DNA Damage, Mutations and Skin Cancer

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