The Experts below are selected from a list of 294 Experts worldwide ranked by ideXlab platform
Kenji Kamiya - One of the best experts on this subject based on the ideXlab platform.
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biochemical properties of the human rev1 protein
FEBS Letters, 2002Co-Authors: Yuji Masuda, Kenji KamiyaAbstract:It has been proposed that the REV1 protein plays an important role in the induced-mutagenesis pathway. We show that purified REV1 protein inserts dCMP opposite template G, A, T and C, and dGMP and dTMP opposite template G in the presence of magnesium, while in the presence of manganese the specificity for dCMP was found to be relaxed and the REV1 protein acquired the ability to insert dCMP, dGMP, dAMP and dTMP opposite templates G, A, T, and C. Kinetic analysis provided evidence for high affinity for dCTP with template G, suggesting that the REV1 protein is specialized for dCTP and template G.
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mechanisms of dcmp transferase reactions catalyzed by mouse rev1 protein
Journal of Biological Chemistry, 2002Co-Authors: Yuji Masuda, Saburo Fukuda, Masaharu Sumii, Mamoru Takahashi, Kenji KamiyaAbstract:Abstract The Rev1 protein, a member of a large family of translesion DNA polymerases, catalyzes a dCMP transfer reaction. Recombinant mouse Rev1 protein was found to insert a dCMP residue opposite guanine, adenine, thymine, cytosine, uracil, and an apurinic/apyrimidinic site and to have weak ability for transfer to a mismatched terminus. The mismatch-extension ability was strongly enhanced by a guanine residue on the template near the mismatched terminus; this was not the case with an apurinic/apyrimidinic site and the other template nucleotides. Kinetic analysis of the dCMP transferase reaction provided evidence for high affinity for dCTP with template G but not the other templates, whereas the template nucleotide did not much affect the V max value. Furthermore, it could be established that the mouse Rev1 protein inserts dGMP and dTMP residues opposite template guanine at aV max similar to that for dCMP.
Nianyun Lin - One of the best experts on this subject based on the ideXlab platform.
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riboflavin vb2 photosensitized oxidation of 2 deoxyguanosine 5 monophosphate dGMP in aqueous solution a transient intermediates study
Physical Chemistry Chemical Physics, 2000Co-Authors: Weizhen Lin, Side Yao, Wenfeng Wang, Zhen-hui Han, Nianyun LinAbstract:The use of time-resolved 337 nm and 248 nm laser flash photolysis with transient absorbance detection has shown direct evidence of electron transfer from dGMP to the triplet state of riboflavin (3RF*). dGMP was used as a DNA model system in order to study the damaging potential of photoexcited riboflavin. The evidence obtained was that: (1) formation of radical anion of riboflavin (RF•−/RFH•) matched the decay of 3RF*; (2) the decay of 3RF* was pseudo-first-order with the concentrations of dGMP, the bimolecular reaction rate constant was determined to be 6.6 × 108 dm3 mol−1 s−1; (3) after the complete decay of 3RF*, the transient absorption spectra of the deprotonated radical cation of dGMP [dGMP(-H)•] was observed in aerated condition for the first time; (4) the addition of N,N,N′,N′-tetramethyl-p-phenylenediamine (TMPD) to the experimental system resulted in the formation of the TMPD radical cation via scavenging dGMP radical cation; and (5) the free energy change (ΔG) from dGMP to 3RF* was calculated to be −43.7 kJ mol−1 with the Rehm–Weller equation, which indicates that photo-oxidation of dGMP attacked by triplet state of riboflavin is thermodynamically possible. Electron-transfer from dGMP to the oxidized radicals of riboflavin is found, which may be another pathway of DNA damage in vivo and in vitro. The direct observation of oxidized guanine radical has provided unambiguously direct initial proof for a photosensitization process of dGMP, with riboflavin as photosensitizer.
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Riboflavin (VB2) photosensitized oxidation of 2′-deoxyguanosine-5′-monophosphate (dGMP) in aqueous solution: a transient intermediates study
Physical Chemistry Chemical Physics, 2000Co-Authors: Weizhen Lin, Side Yao, Wenfeng Wang, Zhen-hui Han, Nianyun LinAbstract:The use of time-resolved 337 nm and 248 nm laser flash photolysis with transient absorbance detection has shown direct evidence of electron transfer from dGMP to the triplet state of riboflavin (3RF*). dGMP was used as a DNA model system in order to study the damaging potential of photoexcited riboflavin. The evidence obtained was that: (1) formation of radical anion of riboflavin (RF•−/RFH•) matched the decay of 3RF*; (2) the decay of 3RF* was pseudo-first-order with the concentrations of dGMP, the bimolecular reaction rate constant was determined to be 6.6 × 108 dm3 mol−1 s−1; (3) after the complete decay of 3RF*, the transient absorption spectra of the deprotonated radical cation of dGMP [dGMP(-H)•] was observed in aerated condition for the first time; (4) the addition of N,N,N′,N′-tetramethyl-p-phenylenediamine (TMPD) to the experimental system resulted in the formation of the TMPD radical cation via scavenging dGMP radical cation; and (5) the free energy change (ΔG) from dGMP to 3RF* was calculated to be −43.7 kJ mol−1 with the Rehm–Weller equation, which indicates that photo-oxidation of dGMP attacked by triplet state of riboflavin is thermodynamically possible. Electron-transfer from dGMP to the oxidized radicals of riboflavin is found, which may be another pathway of DNA damage in vivo and in vitro. The direct observation of oxidized guanine radical has provided unambiguously direct initial proof for a photosensitization process of dGMP, with riboflavin as photosensitizer.
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Pulse radiolytic study of electron transfer reaction for fast repair of the one-electron oxidized radicals of dAMP and dGMP by hydroxycinnamic acid derivatives
Radiation Physics and Chemistry, 1999Co-Authors: Yue Jiang, Side Yao, Weizhen Lin, Nianyun Lin, Dayuan ZhuAbstract:Abstract Using the techniques of pulse radiolysis, it has been demonstrated that the interaction of one-electron-oxidized radicals of dAMP (2'-deoxyadenosine-5-monophosphate) and dGMP (2'-deoxyguanosine-5'-monophosphate), produced by SO − 4 radical reaction, with hydroxycinnamic acid derivatives proceeds via electron transfer reaction. The rate constants of electron transfer from hydroxycinnamic acid derivatives to oxidizing free radicals of dAMP and dGMP were obtained to be (1–3)×10 9 dm 3 mol −1 s −1 .
Alan G Marshall - One of the best experts on this subject based on the ideXlab platform.
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gas phase rna and dna ions 1 h d exchange of the m h anions of nucleoside 5 monophosphates gmp dGMP amp damp cmp dcmp ump dtmp ribose 5 monophosphate and 2 deoxyribose 5 monophosphate with d2o and d2s
Journal of the American Chemical Society, 1998Co-Authors: Michael A. Freitas, And Christopher L Hendrickson, Alan G MarshallAbstract:H/D exchange from D2O and D2S to electrosprayed [M − H]- nucleoside 5‘-monophosphate anions (GMP, dGMP, AMP, dAMP, CMP, dCMP, UMP, TMP) is examined by Fourier transform ion cyclotron resonance mass spectrometry at 9.4 T, along with sugar phosphate controls (ribose 5-monophosphate (R5P) and 2-deoxyribose 5-monophosphate (dR5P)). The relative exchange rates of the nucleotides with D2O were dR5P > dCMP > R5P > CMP > dAMP > UMP > AMP > dTMP ≫ dGMP ≫ GMP, and with D2S were CMP > UMP ≈ dTMP > dCMP > dAMP > AMP > R5P > dR5P ≫ dGMP ≫ GMP. All exchange rates increase dramatically on changing from D2O to D2S, due to the smaller gas-phase acidity difference between exchange reagent and the nucleotide: Δ(ΔHacid) > 60 kcal mol-1 for D2O vs Δ(ΔHacid) > 20 kcal mol-1 for D2S. Ab initio calculations on model compounds at the MP2/6-31+G*//HF/6-31+G* level yield the following order of calculated acidities for each of the exchangeable hydrogens: R2O3PO-H > R2N-H > (R2O-H on ribose) > RN-H2 > (R2O-H on 2-deoxyribose). The ...
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Gas-Phase RNA and DNA Ions. 1. H/D Exchange of the [M − H]- Anions of Nucleoside 5‘-Monophosphates (GMP, dGMP, AMP, dAMP, CMP, dCMP, UMP, dTMP), Ribose 5-Monophosphate, and 2-Deoxyribose 5-Monophosphate with D2O and D2S
Journal of the American Chemical Society, 1998Co-Authors: Michael A. Freitas, And Christopher L Hendrickson, Alan G MarshallAbstract:H/D exchange from D2O and D2S to electrosprayed [M − H]- nucleoside 5‘-monophosphate anions (GMP, dGMP, AMP, dAMP, CMP, dCMP, UMP, TMP) is examined by Fourier transform ion cyclotron resonance mass spectrometry at 9.4 T, along with sugar phosphate controls (ribose 5-monophosphate (R5P) and 2-deoxyribose 5-monophosphate (dR5P)). The relative exchange rates of the nucleotides with D2O were dR5P > dCMP > R5P > CMP > dAMP > UMP > AMP > dTMP ≫ dGMP ≫ GMP, and with D2S were CMP > UMP ≈ dTMP > dCMP > dAMP > AMP > R5P > dR5P ≫ dGMP ≫ GMP. All exchange rates increase dramatically on changing from D2O to D2S, due to the smaller gas-phase acidity difference between exchange reagent and the nucleotide: Δ(ΔHacid) > 60 kcal mol-1 for D2O vs Δ(ΔHacid) > 20 kcal mol-1 for D2S. Ab initio calculations on model compounds at the MP2/6-31+G*//HF/6-31+G* level yield the following order of calculated acidities for each of the exchangeable hydrogens: R2O3PO-H > R2N-H > (R2O-H on ribose) > RN-H2 > (R2O-H on 2-deoxyribose). The ...
Yuji Masuda - One of the best experts on this subject based on the ideXlab platform.
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biochemical properties of the human rev1 protein
FEBS Letters, 2002Co-Authors: Yuji Masuda, Kenji KamiyaAbstract:It has been proposed that the REV1 protein plays an important role in the induced-mutagenesis pathway. We show that purified REV1 protein inserts dCMP opposite template G, A, T and C, and dGMP and dTMP opposite template G in the presence of magnesium, while in the presence of manganese the specificity for dCMP was found to be relaxed and the REV1 protein acquired the ability to insert dCMP, dGMP, dAMP and dTMP opposite templates G, A, T, and C. Kinetic analysis provided evidence for high affinity for dCTP with template G, suggesting that the REV1 protein is specialized for dCTP and template G.
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mechanisms of dcmp transferase reactions catalyzed by mouse rev1 protein
Journal of Biological Chemistry, 2002Co-Authors: Yuji Masuda, Saburo Fukuda, Masaharu Sumii, Mamoru Takahashi, Kenji KamiyaAbstract:Abstract The Rev1 protein, a member of a large family of translesion DNA polymerases, catalyzes a dCMP transfer reaction. Recombinant mouse Rev1 protein was found to insert a dCMP residue opposite guanine, adenine, thymine, cytosine, uracil, and an apurinic/apyrimidinic site and to have weak ability for transfer to a mismatched terminus. The mismatch-extension ability was strongly enhanced by a guanine residue on the template near the mismatched terminus; this was not the case with an apurinic/apyrimidinic site and the other template nucleotides. Kinetic analysis of the dCMP transferase reaction provided evidence for high affinity for dCTP with template G but not the other templates, whereas the template nucleotide did not much affect the V max value. Furthermore, it could be established that the mouse Rev1 protein inserts dGMP and dTMP residues opposite template guanine at aV max similar to that for dCMP.
Weizhen Lin - One of the best experts on this subject based on the ideXlab platform.
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riboflavin vb2 photosensitized oxidation of 2 deoxyguanosine 5 monophosphate dGMP in aqueous solution a transient intermediates study
Physical Chemistry Chemical Physics, 2000Co-Authors: Weizhen Lin, Side Yao, Wenfeng Wang, Zhen-hui Han, Nianyun LinAbstract:The use of time-resolved 337 nm and 248 nm laser flash photolysis with transient absorbance detection has shown direct evidence of electron transfer from dGMP to the triplet state of riboflavin (3RF*). dGMP was used as a DNA model system in order to study the damaging potential of photoexcited riboflavin. The evidence obtained was that: (1) formation of radical anion of riboflavin (RF•−/RFH•) matched the decay of 3RF*; (2) the decay of 3RF* was pseudo-first-order with the concentrations of dGMP, the bimolecular reaction rate constant was determined to be 6.6 × 108 dm3 mol−1 s−1; (3) after the complete decay of 3RF*, the transient absorption spectra of the deprotonated radical cation of dGMP [dGMP(-H)•] was observed in aerated condition for the first time; (4) the addition of N,N,N′,N′-tetramethyl-p-phenylenediamine (TMPD) to the experimental system resulted in the formation of the TMPD radical cation via scavenging dGMP radical cation; and (5) the free energy change (ΔG) from dGMP to 3RF* was calculated to be −43.7 kJ mol−1 with the Rehm–Weller equation, which indicates that photo-oxidation of dGMP attacked by triplet state of riboflavin is thermodynamically possible. Electron-transfer from dGMP to the oxidized radicals of riboflavin is found, which may be another pathway of DNA damage in vivo and in vitro. The direct observation of oxidized guanine radical has provided unambiguously direct initial proof for a photosensitization process of dGMP, with riboflavin as photosensitizer.
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Riboflavin (VB2) photosensitized oxidation of 2′-deoxyguanosine-5′-monophosphate (dGMP) in aqueous solution: a transient intermediates study
Physical Chemistry Chemical Physics, 2000Co-Authors: Weizhen Lin, Side Yao, Wenfeng Wang, Zhen-hui Han, Nianyun LinAbstract:The use of time-resolved 337 nm and 248 nm laser flash photolysis with transient absorbance detection has shown direct evidence of electron transfer from dGMP to the triplet state of riboflavin (3RF*). dGMP was used as a DNA model system in order to study the damaging potential of photoexcited riboflavin. The evidence obtained was that: (1) formation of radical anion of riboflavin (RF•−/RFH•) matched the decay of 3RF*; (2) the decay of 3RF* was pseudo-first-order with the concentrations of dGMP, the bimolecular reaction rate constant was determined to be 6.6 × 108 dm3 mol−1 s−1; (3) after the complete decay of 3RF*, the transient absorption spectra of the deprotonated radical cation of dGMP [dGMP(-H)•] was observed in aerated condition for the first time; (4) the addition of N,N,N′,N′-tetramethyl-p-phenylenediamine (TMPD) to the experimental system resulted in the formation of the TMPD radical cation via scavenging dGMP radical cation; and (5) the free energy change (ΔG) from dGMP to 3RF* was calculated to be −43.7 kJ mol−1 with the Rehm–Weller equation, which indicates that photo-oxidation of dGMP attacked by triplet state of riboflavin is thermodynamically possible. Electron-transfer from dGMP to the oxidized radicals of riboflavin is found, which may be another pathway of DNA damage in vivo and in vitro. The direct observation of oxidized guanine radical has provided unambiguously direct initial proof for a photosensitization process of dGMP, with riboflavin as photosensitizer.
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Pulse radiolytic study of electron transfer reaction for fast repair of the one-electron oxidized radicals of dAMP and dGMP by hydroxycinnamic acid derivatives
Radiation Physics and Chemistry, 1999Co-Authors: Yue Jiang, Side Yao, Weizhen Lin, Nianyun Lin, Dayuan ZhuAbstract:Abstract Using the techniques of pulse radiolysis, it has been demonstrated that the interaction of one-electron-oxidized radicals of dAMP (2'-deoxyadenosine-5-monophosphate) and dGMP (2'-deoxyguanosine-5'-monophosphate), produced by SO − 4 radical reaction, with hydroxycinnamic acid derivatives proceeds via electron transfer reaction. The rate constants of electron transfer from hydroxycinnamic acid derivatives to oxidizing free radicals of dAMP and dGMP were obtained to be (1–3)×10 9 dm 3 mol −1 s −1 .