Biomaterial Database

Effects of glutathione on alkylation and cross-linking of DNA by mitomycin C. Isolation of a ternary glutathione-mitomycin-DNA adduct. 1994

M Sharma, and Q Y He, and M Tomasz

Department of Chemistry, Hunter College, City University of New York, New York 10021.

Mitomycin C (MC), a clinically used antitumor antibiotic, is known to alkylate DNA monofunctionally, and to generate DNA interstrand cross-links by bifunctional alkylation. Both processes are dependent on the reductive activation of MC. Glutathione (GSH) was shown here to cause three types of changes in the pattern of alkylation of DNA by MC: (i) GSH caused a decrease of both the overall covalent binding ratio of MC to Micrococcus luteus DNA and the extent of interstrand cross-linking of 32P-pBR322 DNA, as the concentration of GSH was increased in the reaction media. Approximately 50% inhibition of cross-linking was observed at 20 mM GSH. It is likely that the inhibition is caused by the formation of MC-GSH conjugates competing with DNA alkylation, since both processes are triggered by reductive activation of MC [Sharma, M., and Tomasz, M. (1994) Chem. Res. Toxicol. (preceding paper in this issue)]. (ii) GSH causes a switch from monofunctional to bifunctional activation of MC by the prototype "monofunctional" MC-activating agents H2/PtO2 and NADPH:cytochrome c reductase/NADPH. This was seen by the predominance of bisadducts (i.e., cross-linked adducts) instead of the usual monoadducts in the enzymatic digests of MC-DNA complexes formed in the presence of GSH, as analyzed by HPLC. This finding suggests that GSH participates in the bifunctional activation of MC in vivo. (iii) A ternary MC-GSH-DNA adduct (6) was formed in the presence of GSH both with M. luteus DNA and with a synthetic duplex oligonucleotide; in this adduct the mitosene C1 is linked to N2 of guanine and the mitosene C10 is linked to GSH via sulfur.(ABSTRACT TRUNCATED AT 250 WORDS)

UI	MeSH Term	Description	Entries
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D009251	NADPH-Ferrihemoprotein Reductase	A flavoprotein that catalyzes the reduction of heme-thiolate-dependent monooxygenases and is part of the microsomal hydroxylating system. EC 1.6.2.4.	Cytochrome P-450 Reductase,Ferrihemoprotein P-450 Reductase,NADPH Cytochrome P-450 Oxidoreductase,NADPH Cytochrome P-450 Reductase,NADPH Cytochrome c Reductase,Cytochrome P-450 Oxidase,Cytochrome P450 Reductase,Ferrihemoprotein P450 Reductase,NADPH Cytochrome P450 Oxidoreductase,NADPH Cytochrome P450 Reductase,NADPH-Cytochrome P450 Reductase,NADPH-P450 Reductase,Cytochrome P 450 Oxidase,Cytochrome P 450 Reductase,Ferrihemoprotein P 450 Reductase,NADPH Cytochrome P 450 Oxidoreductase,NADPH Cytochrome P 450 Reductase,NADPH Ferrihemoprotein Reductase,NADPH P450 Reductase,Oxidase, Cytochrome P-450,P-450 Oxidase, Cytochrome,P450 Reductase, Cytochrome,P450 Reductase, NADPH-Cytochrome,Reductase, Cytochrome P-450,Reductase, Cytochrome P450,Reductase, Ferrihemoprotein P-450,Reductase, Ferrihemoprotein P450,Reductase, NADPH-Cytochrome P450,Reductase, NADPH-Ferrihemoprotein,Reductase, NADPH-P450
D009841	Oligonucleotides	Polymers made up of a few (2-20) nucleotides. In molecular genetics, they refer to a short sequence synthesized to match a region where a mutation is known to occur, and then used as a probe (OLIGONUCLEOTIDE PROBES). (Dorland, 28th ed)	Oligonucleotide
D003432	Cross-Linking Reagents	Reagents with two reactive groups, usually at opposite ends of the molecule, that are capable of reacting with and thereby forming bridges between side chains of amino acids in proteins; the locations of naturally reactive areas within proteins can thereby be identified; may also be used for other macromolecules, like glycoproteins, nucleic acids, or other.	Bifunctional Reagent,Bifunctional Reagents,Cross Linking Reagent,Crosslinking Reagent,Cross Linking Reagents,Crosslinking Reagents,Linking Reagent, Cross,Linking Reagents, Cross,Reagent, Bifunctional,Reagent, Cross Linking,Reagent, Crosslinking,Reagents, Bifunctional,Reagents, Cross Linking,Reagents, Cross-Linking,Reagents, Crosslinking
D004269	DNA, Bacterial	Deoxyribonucleic acid that makes up the genetic material of bacteria.	Bacterial DNA
D004591	Electrophoresis, Polyacrylamide Gel	Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.	Polyacrylamide Gel Electrophoresis,SDS-PAGE,Sodium Dodecyl Sulfate-PAGE,Gel Electrophoresis, Polyacrylamide,SDS PAGE,Sodium Dodecyl Sulfate PAGE,Sodium Dodecyl Sulfate-PAGEs
D005978	Glutathione	A tripeptide with many roles in cells. It conjugates to drugs to make them more soluble for excretion, is a cofactor for some enzymes, is involved in protein disulfide bond rearrangement and reduces peroxides.	Reduced Glutathione,gamma-L-Glu-L-Cys-Gly,gamma-L-Glutamyl-L-Cysteinylglycine,Glutathione, Reduced,gamma L Glu L Cys Gly,gamma L Glutamyl L Cysteinylglycine
D000478	Alkylation	The covalent bonding of an alkyl group to an organic compound. It can occur by a simple addition reaction or by substitution of another functional group.	Alkylations
D001483	Base Sequence	The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.	DNA Sequence,Nucleotide Sequence,RNA Sequence,DNA Sequences,Base Sequences,Nucleotide Sequences,RNA Sequences,Sequence, Base,Sequence, DNA,Sequence, Nucleotide,Sequence, RNA,Sequences, Base,Sequences, DNA,Sequences, Nucleotide,Sequences, RNA
D001711	Biotransformation	The chemical alteration of an exogenous substance by or in a biological system. The alteration may inactivate the compound or it may result in the production of an active metabolite of an inactive parent compound. The alterations may be divided into METABOLIC DETOXICATION, PHASE I and METABOLIC DETOXICATION, PHASE II.