Biomaterial Database

Conformations of poly(dG-dC).poly(dG-dC) modified by the O-acetyl derivative of the carcinogen 4-hydroxyaminoquinoline 1-oxide. 1984

B Bailleul, and S Galiègue-Zouitina, and M H Loucheux-Lefebvre

Poly(dG-dC).poly(dG-dC) has been modified by reaction with 4-acetoxyaminoquinoline 1-oxide (Ac-4 HAQO), the ultimate carcinogen of 4-nitroquinoline 1-oxide. The circular dichroism (CD) spectra of the modified and unmodified polymers have been compared under various experimental conditions. The CD spectra were recorded in 1 mM phosphate, 50% (v/v) ethanol, 3.8 M LiCl and 95% (v/v) ethanol, conditions in which poly(dG-dC).poly(dG-dC) adopts the B-, Z-, C- and A-form respectively. In 1 mM phosphate buffer, poly(dG-dC).poly(dG-dC) modified by Ac-4 HAQO seems not to contain regions in the Z-form. Z-form induction could be progressively obtained by the addition of ethanol as follows: in the buffer with about 30% ethanol the modified polymer started to adopt the Z structure, while 40% of ethanol in the buffer was necessary for the unmodified polymer. In the 50% ethanol-1 mM phosphate buffer mixture (v/v), poly(dG-dC).poly(dG-dC) was entirely in the Z-form while poly(dG-dC).poly(dG-dC) modified by Ac-4 HAQO remained partially in the B-form. Enzymatic digestions with the nuclease S1 which is specific of the single-stranded DNA were carried out in order to support the modified poly(dG-dC).poly(dG-dC) CD study conclusions. The role played by the two major adducts on the conformational characteristics of modified polymer is discussed.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D009690	Nucleic Acid Conformation	The spatial arrangement of the atoms of a nucleic acid or polynucleotide that results in its characteristic 3-dimensional shape.	DNA Conformation,RNA Conformation,Conformation, DNA,Conformation, Nucleic Acid,Conformation, RNA,Conformations, DNA,Conformations, Nucleic Acid,Conformations, RNA,DNA Conformations,Nucleic Acid Conformations,RNA Conformations
D011089	Polydeoxyribonucleotides	A group of 13 or more deoxyribonucleotides in which the phosphate residues of each deoxyribonucleotide act as bridges in forming diester linkages between the deoxyribose moieties.	Polydeoxyribonucleotide
D002273	Carcinogens	Substances that increase the risk of NEOPLASMS in humans or animals. Both genotoxic chemicals, which affect DNA directly, and nongenotoxic chemicals, which induce neoplasms by other mechanism, are included.	Carcinogen,Oncogen,Oncogens,Tumor Initiator,Tumor Initiators,Tumor Promoter,Tumor Promoters,Initiator, Tumor,Initiators, Tumor,Promoter, Tumor,Promoters, Tumor
D002851	Chromatography, High Pressure Liquid	Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.	Chromatography, High Performance Liquid,Chromatography, High Speed Liquid,Chromatography, Liquid, High Pressure,HPLC,High Performance Liquid Chromatography,High-Performance Liquid Chromatography,UPLC,Ultra Performance Liquid Chromatography,Chromatography, High-Performance Liquid,High-Performance Liquid Chromatographies,Liquid Chromatography, High-Performance
D002942	Circular Dichroism	A change from planar to elliptic polarization when an initially plane-polarized light wave traverses an optically active medium. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Circular Dichroism, Vibrational,Dichroism, Circular,Vibrational Circular Dichroism
D004720	Endonucleases	Enzymes that catalyze the hydrolysis of the internal bonds and thereby the formation of polynucleotides or oligonucleotides from ribo- or deoxyribonucleotide chains. EC 3.1.-.	Endonuclease
D000634	Aminoquinolines	Quinolines substituted in any position by one or more amino groups.
D013816	Thermodynamics	A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)	Thermodynamic
D015719	Single-Strand Specific DNA and RNA Endonucleases	Enzymes that catalyze the endonucleolytic cleavage of single-stranded regions of DNA or RNA molecules while leaving the double-stranded regions intact. They are particularly useful in the laboratory for producing "blunt-ended" DNA molecules from DNA with single-stranded ends and for sensitive GENETIC TECHNIQUES such as NUCLEASE PROTECTION ASSAYS that involve the detection of single-stranded DNA and RNA.	Single Strand Specific DNA and RNA Endonucleases