Biomaterial Database

The effect of thioketo substitution on uracil-2-aminopurine and uracil-2, 6-diaminopurine interactions in polynucleotides. 1976

C Janion, and K H Scheit

The existence of the complexes poly[r(s4U)] . poly[r(n2h6A] and poly-[r(s4U)] . poly[r(n2A)] was demonstrated by means of spectrophotometric titration and sedimentation veolicty analysis. According to the absorption-temperature profiles thioketo substitution of poly[r(U)] . poly[r(n2h6A)] led to stabilisation of the helical structure, thus implying that the 4-thioketo group does not participate in s4U . n2h6A base pairing. In the case of poly[r(s4U)] . poly[r(n2A)] drastic destabilistaion of the helical structure by thioketo substitution was observed. This indicates that the thioketo substituents participate in s4U .n2A base pairing.

UI	MeSH Term	Description	Entries
D007659	Ketones	Organic compounds containing a carbonyl group	Ketone
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
D009691	Nucleic Acid Denaturation	Disruption of the secondary structure of nucleic acids by heat, extreme pH or chemical treatment. Double strand DNA is "melted" by dissociation of the non-covalent hydrogen bonds and hydrophobic interactions. Denatured DNA appears to be a single-stranded flexible structure. The effects of denaturation on RNA are similar though less pronounced and largely reversible.	DNA Denaturation,DNA Melting,RNA Denaturation,Acid Denaturation, Nucleic,Denaturation, DNA,Denaturation, Nucleic Acid,Denaturation, RNA,Nucleic Acid Denaturations
D011061	Poly A	A group of adenine ribonucleotides in which the phosphate residues of each adenine ribonucleotide act as bridges in forming diester linkages between the ribose moieties.	Adenine Polynucleotides,Polyadenylic Acids,Poly(rA),Polynucleotides, Adenine
D011072	Poly U	A group of uridine ribonucleotides in which the phosphate residues of each uridine ribonucleotide act as bridges in forming diester linkages between the ribose moieties.	Polyuridylic Acids,Uracil Polynucleotides,Poly(rU),Acids, Polyuridylic,Polynucleotides, Uracil
D011117	Polyribonucleotide Nucleotidyltransferase	An enzyme of the transferase class that catalyzes the reaction RNA(n+1) and orthophosphate to yield RNA(n) and a nucleoside diphosphate, or the reverse reaction. ADP, IDP, GDP, UDP, and CDP can act as donors in the latter case. (From Dorland, 27th ed) EC 2.7.7.8.	Polynucleotide Phosphorylase,Nucleotidyltransferase, Polyribonucleotide,Phosphorylase, Polynucleotide
D011119	Polynucleotides	BIOPOLYMERS composed of NUCLEOTIDES covalently bonded in a chain. The most common examples are DNA and RNA chains.	Polynucleotide
D011687	Purines	A series of heterocyclic compounds that are variously substituted in nature and are known also as purine bases. They include ADENINE and GUANINE, constituents of nucleic acids, as well as many alkaloids such as CAFFEINE and THEOPHYLLINE. Uric acid is the metabolic end product of purine metabolism.
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli