Biomaterial Database

The thermodynamics and kinetics of conformational changes in 5-S RNA from Escherichia coli. 1975

R Lecanidou, and E G Richards

Solutions of native, renatured and denatured 5-S RNA from Escherichia coli were each found to revert to a mixture of the denatured and renatured forms when incubated at elevated temperatures in the absence of divalent cations. The equilibrium and rate constants for the renaturation and denaturation reactions were studied as a function of temperature and concentration of added NaCl. The enthalpy and entropy of denaturation and the activation energies were determined. The activation energies for the renaturation reaction were found to be almost independent of the salt concentration, whereas the other parameters increased with the salt concentration. The results are interpreted in terms of a partially unfolded intermediate whose concentration is suppressed by the addition of salt.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008274	Magnesium	A metallic element that has the atomic symbol Mg, atomic number 12, and atomic weight 24.31. It is important for the activity of many enzymes, especially those involved in OXIDATIVE PHOSPHORYLATION.
D008433	Mathematics	The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Mathematic
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
D009695	Nucleic Acid Renaturation	The reformation of all, or part of, the native conformation of a nucleic acid molecule after the molecule has undergone denaturation.	Acid Renaturation, Nucleic,Acid Renaturations, Nucleic,Nucleic Acid Renaturations,Renaturation, Nucleic Acid,Renaturations, Nucleic Acid
D009994	Osmolar Concentration	The concentration of osmotically active particles in solution expressed in terms of osmoles of solute per liter of solution. Osmolality is expressed in terms of osmoles of solute per kilogram of solvent.	Ionic Strength,Osmolality,Osmolarity,Concentration, Osmolar,Concentrations, Osmolar,Ionic Strengths,Osmolalities,Osmolar Concentrations,Osmolarities,Strength, Ionic,Strengths, Ionic
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
D001665	Binding Sites	The parts of a macromolecule that directly participate in its specific combination with another molecule.	Combining Site,Binding Site,Combining Sites,Site, Binding,Site, Combining,Sites, Binding,Sites, Combining
D012329	RNA, Bacterial	Ribonucleic acid in bacteria having regulatory and catalytic roles as well as involvement in protein synthesis.	Bacterial RNA