Nucleic Acids: High molecular weight polymers containing a mixture of purine and pyrimidine nucleotides chained together by ribose or deoxyribose linkages.Carbocysteine: A compound formed when iodoacetic acid reacts with sulfhydryl groups in proteins. It has been used as an anti-infective nasal spray with mucolytic and expectorant action.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.DNA, B-Form: The most common form of DNA found in nature. It is a right-handed helix with 10 base pairs per turn, a pitch of 0.338 nm per base pair and a helical diameter of 1.9 nm.Xanthopterin: 2-Amino-1,5-dihydro-4,6-pteridinedione. Pigment first discovered in butterfly wings and widely distributed in plants and animals.Adenine: A purine base and a fundamental unit of ADENINE NUCLEOTIDES.GuanineCytosine: A pyrimidine base that is a fundamental unit of nucleic acids.UracilBase Pairing: Pairing of purine and pyrimidine bases by HYDROGEN BONDING in double-stranded DNA or RNA.Hydrogen Bonding: A low-energy attractive force between hydrogen and another element. It plays a major role in determining the properties of water, proteins, and other compounds.Peptide Nucleic Acids: DNA analogs containing neutral amide backbone linkages composed of aminoethyl glycine units instead of the usual phosphodiester linkage of deoxyribose groups. Peptide nucleic acids have high biological stability and higher affinity for complementary DNA or RNA sequences than analogous DNA oligomers.Nucleic Acid Conformation: The spatial arrangement of the atoms of a nucleic acid or polynucleotide that results in its characteristic 3-dimensional shape.ThyminePolynucleotidesDNA: A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.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)Acid-Base Equilibrium: The balance between acids and bases in the BODY FLUIDS. The pH (HYDROGEN-ION CONCENTRATION) of the arterial BLOOD provides an index for the total body acid-base balance.Spectrophotometry, Ultraviolet: Determination of the spectra of ultraviolet absorption by specific molecules in gases or liquids, for example Cl2, SO2, NO2, CS2, ozone, mercury vapor, and various unsaturated compounds. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Acid-Base Imbalance: Disturbances in the ACID-BASE EQUILIBRIUM of the body.Pyrimidines: A family of 6-membered heterocyclic compounds occurring in nature in a wide variety of forms. They include several nucleic acid constituents (CYTOSINE; THYMINE; and URACIL) and form the basic structure of the barbiturates.Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Magnetic Resonance Spectroscopy: Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).Water: A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)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.Nucleic Acid Probes: Nucleic acid which complements a specific mRNA or DNA molecule, or fragment thereof; used for hybridization studies in order to identify microorganisms and for genetic studies.Nucleic Acid Amplification Techniques: Laboratory techniques that involve the in-vitro synthesis of many copies of DNA or RNA from one original template.RNA: A polynucleotide consisting essentially of chains with a repeating backbone of phosphate and ribose units to which nitrogenous bases are attached. RNA is unique among biological macromolecules in that it can encode genetic information, serve as an abundant structural component of cells, and also possesses catalytic activity. (Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)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.Nucleic Acid Hybridization: Widely used technique which exploits the ability of complementary sequences in single-stranded DNAs or RNAs to pair with each other to form a double helix. Hybridization can take place between two complimentary DNA sequences, between a single-stranded DNA and a complementary RNA, or between two RNA sequences. The technique is used to detect and isolate specific sequences, measure homology, or define other characteristics of one or both strands. (Kendrew, Encyclopedia of Molecular Biology, 1994, p503)Hydrogen-Ion Concentration: The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Alkalosis: A pathological condition that removes acid or adds base to the body fluids.Catalysis: The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.Acidosis: A pathologic condition of acid accumulation or depletion of base in the body. The two main types are RESPIRATORY ACIDOSIS and metabolic acidosis, due to metabolic acid build up.Alkalies: Usually a hydroxide of lithium, sodium, potassium, rubidium or cesium, but also the carbonates of these metals, ammonia, and the amines. (Grant & Hackh's Chemical Dictionary, 5th ed)Kinetics: The rate dynamics in chemical or physical systems.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)Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Bicarbonates: Inorganic salts that contain the -HCO3 radical. They are an important factor in determining the pH of the blood and the concentration of bicarbonate ions is regulated by the kidney. Levels in the blood are an index of the alkali reserve or buffering capacity.Alkalosis, Respiratory: A state due to excess loss of carbon dioxide from the body. (Dorland, 27th ed)Base Composition: The relative amounts of the PURINES and PYRIMIDINES in a nucleic acid.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.DNA, Bacterial: Deoxyribonucleic acid that makes up the genetic material of bacteria.Crystallography, X-Ray: The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Education, Veterinary: Use for general articles concerning veterinary medical education.Sodium Bicarbonate: A white, crystalline powder that is commonly used as a pH buffering agent, an electrolyte replenisher, systemic alkalizer and in topical cleansing solutions.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.Hypermedia: Computerized compilations of information units (text, sound, graphics, and/or video) interconnected by logical nonlinear linkages that enable users to follow optimal paths through the material and also the systems used to create and display this information. (From Thesaurus of ERIC Descriptors, 1994)Skull Base: The inferior region of the skull consisting of an internal (cerebral), and an external (basilar) surface.Molecular Structure: The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Acids: Chemical compounds which yield hydrogen ions or protons when dissolved in water, whose hydrogen can be replaced by metals or basic radicals, or which react with bases to form salts and water (neutralization). An extension of the term includes substances dissolved in media other than water. (Grant & Hackh's Chemical Dictionary, 5th ed)Schiff Bases: Condensation products of aromatic amines and aldehydes forming azomethines substituted on the N atom, containing the general formula R-N:CHR. (From Grant & Hackh's Chemical Dictionary, 5th ed)Models, Chemical: Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.Substrate Specificity: A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.Gases: The vapor state of matter; nonelastic fluids in which the molecules are in free movement and their mean positions far apart. Gases tend to expand indefinitely, to diffuse and mix readily with other gases, to have definite relations of volume, temperature, and pressure, and to condense or liquefy at low temperatures or under sufficient pressure. (Grant & Hackh's Chemical Dictionary, 5th ed)Catalytic Domain: The region of an enzyme that interacts with its substrate to cause the enzymatic reaction.Molecular Conformation: The characteristic three-dimensional shape of a molecule.Biocatalysis: The facilitation of biochemical reactions with the aid of naturally occurring catalysts such as ENZYMES.Xylosidases: A group of enzymes that catalyze the hydrolysis of alpha- or beta-xylosidic linkages. EC 3.2.1.8 catalyzes the endo-hydrolysis of 1,4-beta-D-xylosidic linkages; EC 3.2.1.32 catalyzes the endo-hydrolysis of 1,3-beta-D-xylosidic linkages; EC 3.2.1.37 catalyzes the exo-hydrolysis of 1,4-beta-D-linkages from the non-reducing termini of xylans; and EC 3.2.1.72 catalyzes the exo-hydrolysis of 1,3-beta-D-linkages from the non-reducing termini of xylans. Other xylosidases have been identified that catalyze the hydrolysis of alpha-xylosidic bonds.Temperature: The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.Protein Binding: The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.Physiology: The biological science concerned with the life-supporting properties, functions, and processes of living organisms or their parts.beta-Glucosidase: An exocellulase with specificity for a variety of beta-D-glycoside substrates. It catalyzes the hydrolysis of terminal non-reducing residues in beta-D-glucosides with release of GLUCOSE.Histidine: An essential amino acid that is required for the production of HISTAMINE.Protons: Stable elementary particles having the smallest known positive charge, found in the nuclei of all elements. The proton mass is less than that of a neutron. A proton is the nucleus of the light hydrogen atom, i.e., the hydrogen ion.RNA, Viral: Ribonucleic acid that makes up the genetic material of viruses.Polymerase Chain Reaction: In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.Mutagenesis, Site-Directed: Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.DNA, Viral: Deoxyribonucleic acid that makes up the genetic material of viruses.Self-Sustained Sequence Replication: An isothermal in-vitro nucleotide amplification process. The process involves the concomitant action of a RNA-DIRECTED DNA POLYMERASE, a ribonuclease (RIBONUCLEASES), and DNA-DIRECTED RNA POLYMERASES to synthesize large quantities of sequence-specific RNA and DNA molecules.Structure-Activity Relationship: The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.DNA, Single-Stranded: A single chain of deoxyribonucleotides that occurs in some bacteria and viruses. It usually exists as a covalently closed circle.Oligodeoxyribonucleotides: A group of deoxyribonucleotides (up to 12) in which the phosphate residues of each deoxyribonucleotide act as bridges in forming diester linkages between the deoxyribose moieties.Ammonium Chloride: An acidifying agent that has expectorant and diuretic effects. Also used in etching and batteries and as a flux in electroplating.Base Pair Mismatch: The presence of an uncomplimentary base in double-stranded DNA caused by spontaneous deamination of cytosine or adenine, mismatching during homologous recombination, or errors in DNA replication. Multiple, sequential base pair mismatches lead to formation of heteroduplex DNA; (NUCLEIC ACID HETERODUPLEXES).Protein Conformation: The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).Stereoisomerism: The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)Sequence Alignment: The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.Buffers: A chemical system that functions to control the levels of specific ions in solution. When the level of hydrogen ion in solution is controlled the system is called a pH buffer.Nucleic Acid Heteroduplexes: Double-stranded nucleic acid molecules (DNA-DNA or DNA-RNA) which contain regions of nucleotide mismatches (non-complementary). In vivo, these heteroduplexes can result from mutation or genetic recombination; in vitro, they are formed by nucleic acid hybridization. Electron microscopic analysis of the resulting heteroduplexes facilitates the mapping of regions of base sequence homology of nucleic acids.DNA Probes: Species- or subspecies-specific DNA (including COMPLEMENTARY DNA; conserved genes, whole chromosomes, or whole genomes) used in hybridization studies in order to identify microorganisms, to measure DNA-DNA homologies, to group subspecies, etc. The DNA probe hybridizes with a specific mRNA, if present. Conventional techniques used for testing for the hybridization product include dot blot assays, Southern blot assays, and DNA:RNA hybrid-specific antibody tests. Conventional labels for the DNA probe include the radioisotope labels 32P and 125I and the chemical label biotin. The use of DNA probes provides a specific, sensitive, rapid, and inexpensive replacement for cell culture techniques for diagnosing infections.Bacterial Proteins: Proteins found in any species of bacterium.RNA, Bacterial: Ribonucleic acid in bacteria having regulatory and catalytic roles as well as involvement in protein synthesis.Sensitivity and Specificity: Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)Glycoside HydrolasesHot Temperature: Presence of warmth or heat or a temperature notably higher than an accustomed norm.Electrons: Stable elementary particles having the smallest known negative charge, present in all elements; also called negatrons. Positively charged electrons are called positrons. The numbers, energies and arrangement of electrons around atomic nuclei determine the chemical identities of elements. Beams of electrons are called CATHODE RAYS.Hydrogen: The first chemical element in the periodic table. It has the atomic symbol H, atomic number 1, and atomic weight [1.00784; 1.00811]. It exists, under normal conditions, as a colorless, odorless, tasteless, diatomic gas. Hydrogen ions are PROTONS. Besides the common H1 isotope, hydrogen exists as the stable isotope DEUTERIUM and the unstable, radioactive isotope TRITIUM.Sequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Aptamers, Nucleotide: Nucleotide sequences, generated by iterative rounds of SELEX APTAMER TECHNIQUE, that bind to a target molecule specifically and with high affinity.Peptides: Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.Protein Structure, Tertiary: The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.Nucleotides: The monomeric units from which DNA or RNA polymers are constructed. They consist of a purine or pyrimidine base, a pentose sugar, and a phosphate group. (From King & Stansfield, A Dictionary of Genetics, 4th ed)Intercalating Agents: Agents that are capable of inserting themselves between the successive bases in DNA, thus kinking, uncoiling or otherwise deforming it and therefore preventing its proper functioning. They are used in the study of DNA.Cloning, Molecular: The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.Oligonucleotide Probes: Synthetic or natural oligonucleotides used in hybridization studies in order to identify and study specific nucleic acid fragments, e.g., DNA segments near or within a specific gene locus or gene. The probe hybridizes with a specific mRNA, if present. Conventional techniques used for testing for the hybridization product include dot blot assays, Southern blot assays, and DNA:RNA hybrid-specific antibody tests. Conventional labels for the probe include the radioisotope labels 32P and 125I and the chemical label biotin.Plasmids: Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.Sequence Homology, Nucleic Acid: The sequential correspondence of nucleotides in one nucleic acid molecule with those of another nucleic acid molecule. Sequence homology is an indication of the genetic relatedness of different organisms and gene function.Skull Base Neoplasms: Neoplasms of the base of the skull specifically, differentiated from neoplasms of unspecified sites or bones of the skull (SKULL NEOPLASMS).DNA Primers: Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques.Polyribonucleotides: A group of 13 or more ribonucleotides in which the phosphate residues of each ribonucleotide act as bridges in forming diester linkages between the ribose moieties.Fluorescent Dyes: Agents that emit light after excitation by light. The wave length of the emitted light is usually longer than that of the incident light. Fluorochromes are substances that cause fluorescence in other substances, i.e., dyes used to mark or label other compounds with fluorescent tags.Nucleosides: Purine or pyrimidine bases attached to a ribose or deoxyribose. (From King & Stansfield, A Dictionary of Genetics, 4th ed)Sequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.Cysteine: A thiol-containing non-essential amino acid that is oxidized to form CYSTINE.Culture Media: Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.RNA, Messenger: RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.Carbon Dioxide: A colorless, odorless gas that can be formed by the body and is necessary for the respiration cycle of plants and animals.G-Quadruplexes: Higher-order DNA and RNA structures formed from guanine-rich sequences. They are formed around a core of at least 2 stacked tetrads of hydrogen-bonded GUANINE bases. They can be formed from one two or four separate strands of DNA (or RNA) and can display a wide variety of topologies, which are a consequence of various combinations of strand direction, length, and sequence. (From Nucleic Acids Res. 2006;34(19):5402-15)Transcription, Genetic: The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.Viruses: Minute infectious agents whose genomes are composed of DNA or RNA, but not both. They are characterized by a lack of independent metabolism and the inability to replicate outside living host cells.DNA-Binding Proteins: Proteins which bind to DNA. The family includes proteins which bind to both double- and single-stranded DNA and also includes specific DNA binding proteins in serum which can be used as markers for malignant diseases.Oligonucleotides, Antisense: Short fragments of DNA or RNA that are used to alter the function of target RNAs or DNAs to which they hybridize.Cell Line: Established cell cultures that have the potential to propagate indefinitely.DNA, Catalytic: Molecules of DNA that possess enzymatic activity.Guanosine: A purine nucleoside that has guanine linked by its N9 nitrogen to the C1 carbon of ribose. It is a component of ribonucleic acid and its nucleotides play important roles in metabolism. (From Dorland, 28th ed)Oxidation-Reduction: A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).Nucleic Acid Renaturation: The reformation of all, or part of, the native conformation of a nucleic acid molecule after the molecule has undergone denaturation.UridineMolecular Diagnostic Techniques: MOLECULAR BIOLOGY techniques used in the diagnosis of disease.Immobilized Nucleic Acids: DNA or RNA bound to a substrate thereby having fixed positions.Ribonucleases: Enzymes that catalyze the hydrolysis of ester bonds within RNA. EC 3.1.-.Denture Bases: The part of a denture that overlies the soft tissue and supports the supplied teeth and is supported in turn by abutment teeth or the residual alveolar ridge. It is usually made of resins or metal or their combination.Proteins: Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.Databases, Nucleic Acid: Databases containing information about NUCLEIC ACIDS such as BASE SEQUENCE; SNPS; NUCLEIC ACID CONFORMATION; and other properties. Information about the DNA fragments kept in a GENE LIBRARY or GENOMIC LIBRARY is often maintained in DNA databases.Viral Proteins: Proteins found in any species of virus.Glutamic Acid: A non-essential amino acid naturally occurring in the L-form. Glutamic acid is the most common excitatory neurotransmitter in the CENTRAL NERVOUS SYSTEM.Molecular Probe Techniques: The use of devices which use detector molecules to detect, investigate, or analyze other molecules, macromolecules, molecular aggregates, or organisms.RNA, Ribosomal: The most abundant form of RNA. Together with proteins, it forms the ribosomes, playing a structural role and also a role in ribosomal binding of mRNA and tRNAs. Individual chains are conventionally designated by their sedimentation coefficients. In eukaryotes, four large chains exist, synthesized in the nucleolus and constituting about 50% of the ribosome. (Dorland, 28th ed)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)Time Factors: Elements of limited time intervals, contributing to particular results or situations.SELEX Aptamer Technique: A method of generating a large library of randomized nucleotides and selecting NUCLEOTIDE APTAMERS by iterative rounds of in vitro selection. A modified procedure substitutes AMINO ACIDS in place of NUCLEOTIDES to make PEPTIDE APTAMERS.Software: Sequential operating programs and data which instruct the functioning of a digital computer.DNA Repair: The reconstruction of a continuous two-stranded DNA molecule without mismatch from a molecule which contained damaged regions. The major repair mechanisms are excision repair, in which defective regions in one strand are excised and resynthesized using the complementary base pairing information in the intact strand; photoreactivation repair, in which the lethal and mutagenic effects of ultraviolet light are eliminated; and post-replication repair, in which the primary lesions are not repaired, but the gaps in one daughter duplex are filled in by incorporation of portions of the other (undamaged) daughter duplex. Excision repair and post-replication repair are sometimes referred to as "dark repair" because they do not require light.RNA, Transfer: The small RNA molecules, 73-80 nucleotides long, that function during translation (TRANSLATION, GENETIC) to align AMINO ACIDS at the RIBOSOMES in a sequence determined by the mRNA (RNA, MESSENGER). There are about 30 different transfer RNAs. Each recognizes a specific CODON set on the mRNA through its own ANTICODON and as aminoacyl tRNAs (RNA, TRANSFER, AMINO ACYL), each carries a specific amino acid to the ribosome to add to the elongating peptide chains.Virology: The study of the structure, growth, function, genetics, and reproduction of viruses, and VIRUS DISEASES.RNA Probes: RNA, usually prepared by transcription from cloned DNA, which complements a specific mRNA or DNA and is generally used for studies of virus genes, distribution of specific RNA in tissues and cells, integration of viral DNA into genomes, transcription, etc. Whereas DNA PROBES are preferred for use at a more macroscopic level for detection of the presence of DNA/RNA from specific species or subspecies, RNA probes are preferred for genetic studies. Conventional labels for the RNA probe include radioisotope labels 32P and 125I and the chemical label biotin. RNA probes may be further divided by category into plus-sense RNA probes, minus-sense RNA probes, and antisense RNA probes.Molecular Probes: A group of atoms or molecules attached to other molecules or cellular structures and used in studying the properties of these molecules and structures. Radioactive DNA or RNA sequences are used in MOLECULAR GENETICS to detect the presence of a complementary sequence by NUCLEIC ACID HYBRIDIZATION.RNA, Double-Stranded: RNA consisting of two strands as opposed to the more prevalent single-stranded RNA. Most of the double-stranded segments are formed from transcription of DNA by intramolecular base-pairing of inverted complementary sequences separated by a single-stranded loop. Some double-stranded segments of RNA are normal in all organisms.Deoxyribonucleases: Enzymes which catalyze the hydrolases of ester bonds within DNA. EC 3.1.-.Chemistry: A basic science concerned with the composition, structure, and properties of matter; and the reactions that occur between substances and the associated energy exchange.Spectrometry, Fluorescence: Measurement of the intensity and quality of fluorescence.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.Repetitive Sequences, Nucleic Acid: Sequences of DNA or RNA that occur in multiple copies. There are several types: INTERSPERSED REPETITIVE SEQUENCES are copies of transposable elements (DNA TRANSPOSABLE ELEMENTS or RETROELEMENTS) dispersed throughout the genome. TERMINAL REPEAT SEQUENCES flank both ends of another sequence, for example, the long terminal repeats (LTRs) on RETROVIRUSES. Variations may be direct repeats, those occurring in the same direction, or inverted repeats, those opposite to each other in direction. TANDEM REPEAT SEQUENCES are copies which lie adjacent to each other, direct or inverted (INVERTED REPEAT SEQUENCES).Oligoribonucleotides: A group of ribonucleotides (up to 12) in which the phosphate residues of each ribonucleotide act as bridges in forming diester linkages between the ribose moieties.Chemical Phenomena: The composition, conformation, and properties of atoms and molecules, and their reaction and interaction processes.RNA-Binding Proteins: Proteins that bind to RNA molecules. Included here are RIBONUCLEOPROTEINS and other proteins whose function is to bind specifically to RNA.Ribonuclease H: A ribonuclease that specifically cleaves the RNA moiety of RNA:DNA hybrids. It has been isolated from a wide variety of prokaryotic and eukaryotic organisms as well as RETROVIRUSES.RNA, Catalytic: RNA that has catalytic activity. The catalytic RNA sequence folds to form a complex surface that can function as an enzyme in reactions with itself and other molecules. It may function even in the absence of protein. There are numerous examples of RNA species that are acted upon by catalytic RNA, however the scope of this enzyme class is not limited to a particular type of substrate.Proflavine: Topical antiseptic used mainly in wound dressings.Species Specificity: The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.Templates, Genetic: Macromolecular molds for the synthesis of complementary macromolecules, as in DNA REPLICATION; GENETIC TRANSCRIPTION of DNA to RNA, and GENETIC TRANSLATION of RNA into POLYPEPTIDES.Carbon Isotopes: Stable carbon atoms that have the same atomic number as the element carbon, but differ in atomic weight. C-13 is a stable carbon isotope.Reverse Transcriptase Polymerase Chain Reaction: A variation of the PCR technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard PCR protocols.TritiumGenes: A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Poly G: A group of guanine ribonucleotides in which the phosphate residues of each guanine ribonucleotide act as bridges in forming diester linkages between the ribose moieties.ComputersReverse Transcription: The biosynthesis of DNA carried out on a template of RNA.2-Aminopurine: A purine that is an isomer of ADENINE (6-aminopurine).Solutions: The homogeneous mixtures formed by the mixing of a solid, liquid, or gaseous substance (solute) with a liquid (the solvent), from which the dissolved substances can be recovered by physical processes. (From Grant & Hackh's Chemical Dictionary, 5th ed)Ribose: A pentose active in biological systems usually in its D-form.Poly A-U: A double-stranded polyribonucleotide comprising polyadenylic and polyuridylic acids.Electrophoresis, Agar Gel: Electrophoresis in which agar or agarose gel is used as the diffusion medium.Reagent Kits, Diagnostic: Commercially prepared reagent sets, with accessory devices, containing all of the major components and literature necessary to perform one or more designated diagnostic tests or procedures. They may be for laboratory or personal use.Specimen Handling: Procedures for collecting, preserving, and transporting of specimens sufficiently stable to provide accurate and precise results suitable for clinical interpretation.Indicators and Reagents: Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499)Methods: A series of steps taken in order to conduct research.Reproducibility of Results: The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.DNA-Directed DNA Polymerase: DNA-dependent DNA polymerases found in bacteria, animal and plant cells. During the replication process, these enzymes catalyze the addition of deoxyribonucleotide residues to the end of a DNA strand in the presence of DNA as template-primer. They also possess exonuclease activity and therefore function in DNA repair.Cattle: Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.Saccharomyces cerevisiae: A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.Ethidium: A trypanocidal agent and possible antiviral agent that is widely used in experimental cell biology and biochemistry. Ethidium has several experimentally useful properties including binding to nucleic acids, noncompetitive inhibition of nicotinic acetylcholine receptors, and fluorescence among others. It is most commonly used as the bromide.Cytidine: A pyrimidine nucleoside that is composed of the base CYTOSINE linked to the five-carbon sugar D-RIBOSE.Molecular Biology: A discipline concerned with studying biological phenomena in terms of the chemical and physical interactions of molecules.DNA Replication: The process by which a DNA molecule is duplicated.HeLa Cells: The first continuously cultured human malignant CELL LINE, derived from the cervical carcinoma of Henrietta Lacks. These cells are used for VIRUS CULTIVATION and antitumor drug screening assays.Microscopy, Electron: Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.Poly C: A group of cytosine ribonucleotides in which the phosphate residues of each cytosine ribonucleotide act as bridges in forming diester linkages between the ribose moieties.HIV-1: The type species of LENTIVIRUS and the etiologic agent of AIDS. It is characterized by its cytopathic effect and affinity for the T4-lymphocyte.DNA Helicases: Proteins that catalyze the unwinding of duplex DNA during replication by binding cooperatively to single-stranded regions of DNA or to short regions of duplex DNA that are undergoing transient opening. In addition DNA helicases are DNA-dependent ATPases that harness the free energy of ATP hydrolysis to translocate DNA strands.Recombinant Proteins: Proteins prepared by recombinant DNA technology.Bacteriological Techniques: Techniques used in studying bacteria.AcridinesBiosensing Techniques: Any of a variety of procedures which use biomolecular probes to measure the presence or concentration of biological molecules, biological structures, microorganisms, etc., by translating a biochemical interaction at the probe surface into a quantifiable physical signal.Phosphorothioate Oligonucleotides: Modified oligonucleotides in which one of the oxygens of the phosphate group is replaced with a sulfur atom.Protein Biosynthesis: The biosynthesis of PEPTIDES and PROTEINS on RIBOSOMES, directed by MESSENGER RNA, via TRANSFER RNA that is charged with standard proteinogenic AMINO ACIDS.Polymers: Compounds formed by the joining of smaller, usually repeating, units linked by covalent bonds. These compounds often form large macromolecules (e.g., BIOPOLYMERS; PLASTICS).Antisense Elements (Genetics): Nucleic acids which hybridize to complementary sequences in other target nucleic acids causing the function of the latter to be affected.Restriction Mapping: Use of restriction endonucleases to analyze and generate a physical map of genomes, genes, or other segments of DNA.DNA, Complementary: Single-stranded complementary DNA synthesized from an RNA template by the action of RNA-dependent DNA polymerase. cDNA (i.e., complementary DNA, not circular DNA, not C-DNA) is used in a variety of molecular cloning experiments as well as serving as a specific hybridization probe.Ultraviolet Rays: That portion of the electromagnetic spectrum immediately below the visible range and extending into the x-ray frequencies. The longer wavelengths (near-UV or biotic or vital rays) are necessary for the endogenous synthesis of vitamin D and are also called antirachitic rays; the shorter, ionizing wavelengths (far-UV or abiotic or extravital rays) are viricidal, bactericidal, mutagenic, and carcinogenic and are used as disinfectants.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Inverted Repeat Sequences: Copies of nucleic acid sequence that are arranged in opposing orientation. They may lie adjacent to each other (tandem) or be separated by some sequence that is not part of the repeat (hyphenated). They may be true palindromic repeats, i.e. read the same backwards as forward, or complementary which reads as the base complement in the opposite orientation. Complementary inverted repeats have the potential to form hairpin loop or stem-loop structures which results in cruciform structures (such as CRUCIFORM DNA) when the complementary inverted repeats occur in double stranded regions.Static Electricity: The accumulation of an electric charge on a objectTransfection: The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.Promoter Regions, Genetic: DNA sequences which are recognized (directly or indirectly) and bound by a DNA-dependent RNA polymerase during the initiation of transcription. Highly conserved sequences within the promoter include the Pribnow box in bacteria and the TATA BOX in eukaryotes.DNA, A-Form: An isoform of DNA that occurs in an environment rich in SODIUM and POTASSIUM ions. It is a right-handed helix with 11 base pairs per turn, a pitch of 0.256 nm per base pair and a helical diameter of 2.3 nm.
Left: the nucleotide base pairs that can form in double-stranded DNA. Between A and T there are two hydrogen bonds, while there ... Both types of molecules complement each other and can only base pair with the opposing type of nucleobase. In nucleic acid, ... DNA and RNA base pair complementarity[edit]. Complementarity between two antiparallel strands of DNA. The top strand goes from ... A complementary strand of DNA or RNA may be constructed based on nucleobase complementarity.[2] Each base pair, A=T vs. G≡C, ...
"Base-stacking and base-pairing contributions into thermal stability of the DNA double helix". Nucleic Acids Research. 34 (2): ... Base pairing. Further information: Base pair. In a DNA double helix, each type of nucleobase on one strand bonds with just one ... of double-stranded DNA by the telomere strand disrupting the double-helical DNA and base pairing to one of the two strands. ... For an intercalator to fit between base pairs, the bases must separate, distorting the DNA strands by unwinding of the double ...
Single-stranded RNA can also be detected, since it usually folds back onto itself and thus provides local base pairing for the ... Ethidium bromide is commonly used to detect nucleic acids in molecular biology laboratories. In the case of DNA this is usually ... Ethidium bromide is thought to act as a mutagen because it intercalates double stranded DNA (i.e., inserts itself between the ... It is added to running buffer and binds by intercalating between DNA base pairs. When the agarose gel is illuminated using UV ...
... by base-pairing with the template (presumably as occurs between DNA strands in the double helix), would carry the amino acids ... This makes nucleic acids good at recognising each other, but poor at distinguishing the varied side chains of amino acids. It ... Crick proposed that each amino acid is first attached to its own specific "adaptor" piece of nucleic acid (in an enzyme- ... nucleic acids and proteins. The amino acids are characterised by having a variety of side chains which vary from being ...
In a DNA double helix, the strands run in opposite directions to permit base pairing between them, which is essential for ... is the end-to-end chemical orientation of a single strand of nucleic acid. In a single strand of DNA or RNA, the chemical ... Transcription of single-stranded RNA from a double-stranded DNA template requires the selection of one strand of the DNA ... The relative positions of structures along a strand of nucleic acid, including genes and various protein binding sites, are ...
Both types of molecules complement each other and can only base pair with the opposing type of nucleobase. In nucleic acid, ... the complementary bases of the two strands form up and begin to unwind the hairpins until a double-stranded RNA (dsRNA) complex ... A complementary strand of DNA or RNA may be constructed based on nucleobase complementarity. Each base pair, A=T vs. G≡C, takes ... Nucleic acids strands may also form hybrids in which single stranded DNA may readily anneal with complementary DNA or RNA. This ...
Because of the complementary nature of base-pairing between nucleic acid polymers, a double-stranded DNA molecule will be ... Example with double-stranded DNA[edit]. DNA strand 1: antisense strand (transcribed to) → RNA strand (sense). DNA strand 2: ... but the complementary base-pairing by which nucleic acid polymerization occurs means that the sequence of the RNA transcript ... the sense of a nucleic acid molecule, particularly of a strand of DNA or RNA, refers to the nature of the roles of the strand ...
... is a common unit of length for single-stranded nucleic acids, similar to how base pair is a unit of length for double-stranded ... the two strands are oriented in opposite directions, which permits base pairing and complementarity between the base-pairs, all ... Nucleic acids then are polymeric macromolecules assembled from nucleotides, the monomer-units of nucleic acids. The purine ... Molecular and cellular biology portal Biology Chromosome Gene Genetics Nucleic acid analogues Nucleic acid sequence Nucleobase ...
Double-stranded nucleic acids are made up of complementary sequences, in which extensive Watson-Crick base pairing results in a ... and include peptide nucleic acid, morpholino- and locked nucleic acid, glycol nucleic acid, and threose nucleic acid. Each of ... Nucleic Acids Research journal Nucleic Acids Book (free online book on the chemistry and biology of nucleic acids) Molecular ... acid methods Nucleic acid structure Nucleic acid thermodynamics Oligonucleotide synthesis Quantification of nucleic acids He ...
At least one set of new base pairs has been announced as of May 2014. Nucleoside Nucleotide Nucleic acid notation Nucleic acid ... In the double helix of DNA, the two strands are oriented chemically in opposite directions, which permits base pairing by ... so those three bases are called the pyrimidine bases. Each of the base pairs in a typical double-helix DNA comprises a purine ... bases that have been modified after the nucleic acid chain has been formed. In DNA, the most common modified base is 5- ...
... means for complementary sequences of single-stranded DNA or RNA to pair by hydrogen bonds to form a double-stranded ... Because cytosine / guanine base-pairing is generally stronger than adenine / thymine base-pairing, the amount of cytosine and ... Nucleic acid thermodynamics is the study of how temperature affects the nucleic acid structure of double-stranded DNA (dsDNA). ... elegantly describe the thermodynamic parameters for forming double-stranded nucleic acid AB from single-stranded nucleic acids ...
In DNA double helix, the two strands of DNA are held together by hydrogen bonds. The nucleotides on one strand base pairs with ... DNA supercoil Gene structure Non-helical models of DNA structure Nucleic acid design Nucleic acid double helix Nucleic acid ... A purine base always pairs with a pyrimidine base (guanine (G) pairs with cytosine (C) and adenine (A) pairs with thymine (T) ... Base pairing in RNA occurs when RNA folds between complementarity regions. Both single- and double-stranded regions are often ...
The nucleic acid double helix is a spiral polymer, usually right-handed, containing two nucleotide strands which base pair ... "Base-stacking and base-pairing contributions into thermal stability of the DNA double helix". Nucleic Acids Research. 34 (2): ... Nucleic acid secondary structure is the basepairing interactions within a single nucleic acid polymer or between two polymers. ... It can be represented as a list of bases which are paired in a nucleic acid molecule. The secondary structures of biological ...
Base-stacking and base-pairing contributions into thermal stability of the DNA double helix. Nucleic Acids Research 2006 34(2): ... Intramolecular base pairs can occur within single-stranded nucleic acids. This is particularly important in RNA molecules (e.g ... Nucleic acids Res. 37, e14 Yamashige, R.; et al. "Highly specific unnatural base pair systems as a third base pair for PCR ... March 2012). "Highly specific unnatural base pair systems as a third base pair for PCR amplification". Nucleic Acids Res. 40 (6 ...
... "base pairs" or "kb" (for thousands of base pairs) depending upon whether single- or double-stranded nucleic acid has been ... Double-stranded DNA moves at a rate that is approximately inversely proportional to the logarithm of the number of base pairs. ... Once the nucleic acid is properly prepared, the samples of the nucleic acid solution are placed in the wells of the gel and a ... Voltage is, however, not the sole factor in determining electrophoresis of nucleic acids. The nucleic acid to be separated can ...
Five consecutive copper-hydroxypyridone base pairs were incorporated into a double strand, which were flanked by only one ... 2009). "Nucleic acid base analog FRET-pair facilitating detailed structural measurements in nucleic acid containing systems". J ... 2012). "Highly specific unnatural base pair systems as a third base pair for PCR amplification". Nucleic Acids Research. 40 (6 ... Artificial nucleic acids include peptide nucleic acid (PNA), Morpholino and locked nucleic acid (LNA), as well as glycol ...
The function of the domain is double stranded-RNA-guided hydrolysis of single stranded-RNA that has been determined in the ... The piwi domain is a protein domain found in piwi proteins and a large number of related nucleic acid-binding proteins, ... This complex binds and cleaves complementary base pairing messenger RNA, destroying it and preventing its translation into ... and which are normally derived exclusively from the antisense strand of double-stranded RNA. piRNAs have thus been classified ...
... are important in base pairing of strands to form higher-level secondary and tertiary structure such as the famed double helix. ... If one strand of the double-stranded DNA is considered the sense strand, then the other strand, considered the antisense strand ... The sequence of nucleobases on a nucleic acid strand is translated by cell machinery into a sequence of amino acids making up a ... Although DNA and RNA nucleotide bases are more similar to each other than are amino acids, the conservation of base pairs can ...
"Base-stacking and base-pairing contributions into thermal stability of the DNA double helix". Nucleic Acids Res. 34 (2): 564-74 ... factor of thermal stability of double stranded nucleic acids is actually due to the base stackings of adjacent bases, rather ... "Base-stacking and base-pairing contributions into thermal stability of the DNA double helix". Nucleic Acids Research. 34 (2): ... The AU base pairs are less stable than the GC base pairs previously attributed to GC bonds containing 3 hydrogen bonds and AU ...
A non-canonical base pairing is an interaction between two bases of a nucleic acid other than the standard base pairings, which ... They are typically less stable than standard base pairings. The presence of non-canonical base pairs in double stranded DNA ... 2006). "Non-Canonical Base Pairs and Higher Order Structures in Nucleic Acids: Crystal Structure Database Analysis". Journal of ... "RNA canonical and non-canonical base pairing types: a recognition method and complete repertoire". Nucleic Acids Res. 30 (19): ...
"Base-stacking and base-pairing contributions into thermal stability of the DNA double helix". Nucleic Acids Research. 34 (2): ... Intramolecular base pairs can occur within single-stranded nucleic acids. This is particularly important in RNA molecules (e.g ... "Highly specific unnatural base pair systems as a third base pair for PCR amplification". Nucleic Acids Research. 40 (6): 2793- ... "Highly specific unnatural base pair systems as a third base pair for PCR amplification". Nucleic Acids Research. 40 (6): 2793- ...
... suggesting normal base-pairing. They interpreted their data as supporting the possibility that the two strands inside the ... The discovery of topoisomerases, enzymes that can change the linking number of circular nucleic acids and thus "unwind" the ... One key observation in support of a double-helical structure is that the individual single strands of small circular viral and ... instead of one fully right-handed helical twist every 10 base pairs, there is only a half-twist of 5 base pairs' length, ...
... the nucleic acid strands may re-anneal imperfectly resulting in the improper pairing of bases. The non-covalent interactions ... Antiparellel strands in DNA double helices are non-covalently bound by hydrogen bonding between Watson and Crick base pairs; ... Acidic nucleic acid denaturants include: Acetic acid HCl Nitric Acid Basic nucleic acid denaturants include: NaOH Other nucleic ... Acetic acid Trichloroacetic acid 12% in water Sulfosalicylic acid Bases work similarly to acids in denaturation. They include: ...
The first NMR spectrum of a double-helical DNA was published in 1977 using a synthetic, 30-base-pair double helix. To overcome ... deoxyadenosine are incorporated into the nucleic acid strand, as natural nucleic acids do not contain any fluorine atoms. 1H ... Nucleic acid NMR uses techniques similar to those of protein NMR, but has several differences. Nucleic acids have a smaller ... Because nucleic acids have a relatively large number of protons which are solvent-exchangeable, nucleic acid NMR is generally ...
But only one of the two single-stranded RNA here will be utilized to base pair with target mRNA. It is known as the guide ... silencing pathways process long RNAs into small RNAs that direct the repression of transcription or translation of nucleic acid ... Dicer cleaves long double-stranded RNA molecules into short double stranded fragments of around 20 nucleotide siRNAs. The dsRNA ... the passenger strand and the guide strand. Consequently, the passenger strand is degraded, while the guide strand is ...
Coleoids rely mostly on ADAR enzymes for RNA editing, which requires large double-stranded RNA structures to flank to the ... Octopuses and other coleoid cephalopods are capable of greater RNA editing (which involves changes to the nucleic acid sequence ... The arms can be described based on side and sequence position (such as L1, R1, L2, R2) and divided into four pairs.[23][22] The ... Two possible extant cephalopod phylogenies, based on genetics studies by Strugnell et al. 2007, are shown in the possible ...
Secondary structures are the base-pairing interactions within a single nucleic acid polymer or between two polymers. DNA has ... mainly fully base-paired double helices, but RNA is single stranded and can form complicated interactions. ... Nucleic Acids Research. Funder. National Institutes of Health, National Science Foundation, Medical Research Foundation of ... RNA works with DNA, the other nucleic acid - so named because they were first discovered in the cell nuclei of living things - ...
"Base-stacking and base-pairing contributions into thermal stability of the DNA double helix". Nucleic Acids Research. 34 (2): ... Base pairing. Further information: Base pair. In a DNA double helix, each type of nucleobase on one strand bonds with just one ... of double-stranded DNA by the telomere strand disrupting the double-helical DNA and base pairing to one of the two strands. ... For an intercalator to fit between base pairs, the bases must separate, distorting the DNA strands by unwinding of the double ...
This has implications for biologically relevant nucleic acids with interspersed regions of paired and unpaired bases. In the ... We also show that nucleic acid flexibility is influenced by local environment (an adjoining double helix). Our results ... ion-nucleic acid interactions. Nucleic acids in the cell are dynamic and undergo structural changes as they transmit and ... The non-OSF scaling of rU40 in NaCl, and of both nucleic acids in MgCl2, may indicate that more complex ion-nucleic acid ...
The methods involve introducing a sample suspected of containing a nucleic acid analyte into a device in accordance with the ... at least one of the additional chambers containing reagents for carrying out an assay for the determination of a nucleic acid ... Devices and methods for carrying out an assay for the determination of nucleic acids are disclosed. The devices comprise (a) a ... When complementary single stranded nucleic acids are incubated together, the complementary base sequences pair to form double ...
Left: the nucleotide base pairs that can form in double-stranded DNA. Between A and T there are two hydrogen bonds, while there ... Both types of molecules complement each other and can only base pair with the opposing type of nucleobase. In nucleic acid, ... DNA and RNA base pair complementarity[edit]. Complementarity between two antiparallel strands of DNA. The top strand goes from ... A complementary strand of DNA or RNA may be constructed based on nucleobase complementarity.[2] Each base pair, A=T vs. G≡C, ...
... "base pairs" or "kb" (for thousands of base pairs) depending upon whether single- or double-stranded nucleic acid has been ... Double-stranded DNA moves at a rate that is approximately inversely proportional to the logarithm of the number of base pairs. ... Once the nucleic acid is properly prepared, the samples of the nucleic acid solution are placed in the wells of the gel and a ... Voltage is, however, not the sole factor in determining electrophoresis of nucleic acids. The nucleic acid to be separated can ...
Base pair: two bases, one in each strand of a double-stranded nucleic acid molecule that are attracted to each other by weak ... Nucleotide pairs: two nucleotides, one in each strand of a double-stranded nucleic acid molecule, that are attracted to each ... Nucleotide: one of the building blocks of nucleic acids. A nucleotide is composed of three parts: a base, a sugar, and a ... that forms part of one of the nucleotide links of a nucleic acid chain. The four different bases are adenine (A), thymine (T), ...
... acid sequence contained in a nucleic acid or mixture thereof comprises treating separate complementary strands of the nucleic ... If the nucleic acid is double-stranded, the nucleotide variation in sequence becomes a base pair variation in sequence. ... which nucleic acid(s) when double-stranded consist of two separated complementary strands, and which nucleic acid(s) are ... to the single-stranded nucleic acid and will hybridize with the nucleic acid strand to form a duplex of strands of unequal ...
... a strand invasion system and an oligonucleotide, wherein the upstream and do ... An isothermal process for amplifying a nucleic acid target molecule that relies on an upstream primer, a downstream primer, ... bases of double-stranded DNA; adenine-uracil (A-U) base pairs can also form by hydrogen bonding in DNA-RNA or RNA-RNA duplexes ... The pairing of nucleic acid strands for determining the presence or absence of a given nucleic acid molecule is commonly called ...
... making it possible to fabricate complicated shapes from a single strand of RNA. Unlike existing methods for folding DNA ... RNA is a nucleic acid composed of A, U, C and G nucleotides. While RNA base pairing mostly joins A with U and C with G, RNA is ... able to form many additional base-pairing possibilities. * In a similar manner to DNA, RNA can form double helices. However, ... The strongest base pairs in RNA are G-C, A-U and G-U, but many other base pairs can form in RNA as well. By contrast, DNA only ...
... digest of larger double-stranded nucleic acids and strand separation or by enzymatic synthesis using a nucleic acid template. ... This is possible because of the inherent base-pairing properties of the nucleic acids; A recognizes T, and G recognizes C. This ... nucleic acid sequence; with. (ii) a nucleic acid-containing sample containing the preselected nucleic acid base ("target") ... Where the nucleic acid containing a target sequence is in a double-stranded (ds) form, it is preferred to first denature the ...
Base-pairing in a siRNA (small interfering RNA) segment, a double-stranded type of RNA. Hydrogen atoms are not shown. ... The most common nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). The main role of DNA is the long-term ... Left: An RNA strand, with its nitrogenous bases. Right: Double-stranded DNA. ... contain extensively base paired regions that have folded together to form double stranded helices. Structural analysis of these ...
... but otherwise delivers unspecific alkylation in single-stranded nucleic acids (compare entries 1-5 in Table 3). In contrast ... Single-stranded. 37. Multiple alkylations. Longer sequences can be targeted. 6. d(CGAACGTTTTTCGTTCG). 0. No reaction. Double- ... It seems that if the N-H bonds are engaged in Watson-Crick base-pairing they are unavailable for reaction with the rhodium. ... a Conversion based on the oligonucleotide; the diazo substrate is typically completely consumed when nucleic acids are present. ...
... adenine forms a base pair with thymine (or uracil) and guanine with cytosine in a double-stranded nucleic acid molecule. ... base pair a pair of hydrogen-bonded nitrogenous bases (one purine and one pyrimidine) that join the component strands of the ... DNA hybridization -- a technique for selectively binding specific segments of single-stranded (ss) DNA or RNA by base pairing ... DNA double helix. Base sequence -- a partnership of organic bases found in DNA and RNA; ...
... are a family of macromolecules that includes deoxyribonucleic acid (DNA ) and multiple forms of ribonucleic acid (RNA ). DNA, ... Their theory was that the nucleic acid DNA was made up of two twisted strands that are held together by base pairs that make up ... All nucleic acids are linear, nonbranching polymers of nucleotides, and are therefore polynucleotides. DNA is double-stranded ... Nucleic acid. Two nucleic acids, deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) , are found in living things which ...
... while RNA consists of nucleic acid, adenine(A), guanine(G), cytosine(C), and uracil (U). RNA is usually single stranded while ... Genes are composed of DNA, which contains information coded in the base pair sequences. They are then used as the blueprint for ... DNA is always double stranded. RNA can be found in both the nucleus and the cytoplasm. There are several types of RNA, all of ... In transcription, information coded in the base sequence of DNA is transcribed into a strand of mRNA that leaves the nucleus ...
... short interfering nucleic acid (siNA), short interfering RNA (siRNA), double-stranded RNA (dsRNA), micro-RNA (miRNA) or short ... methods and kits may include nucleic acid molecules (for example, ... represents base pairing between the ribonucleotides; wherein each of A, C, G and U is independently an unmodified or ... The double stranded nucleic acid molecule of claim 3, wherein each of Z and Z is present.. 6. The double stranded nucleic acid ...
Other methylations of the bases or of the deoxyribose are sometimes induced by carcinogens. These usually lead to mispairing of ... Nucleic acid - Methylation: Three types of natural methylation have been reported in DNA. Cytosine can be modified either on ... they recognize specific sequences within the DNA molecule so that only a subset of the bases is modified. ... In DNA, which is usually double-stranded, the bases in one strand pair with complementary bases in a second DNA strand. In RNA ...
Here electrochemically we probe CT in the three primary conformations of double-stranded nucleic acids, A-, B-, and Z-form DNA ... Jun, 2002 , Pubmed ID: 12127450 The base pair stack within double helical DNA provides an effective medium for charge transport ... Electrochemical sensors have also been developed, based upon the sensitivity of DNA charge transport to base pair stacking, and ... chemistry is sensitive to DNA structure and base pair stacking. In an electrochemical assay based upon DNA CT, DNA-modified ...
Single-stranded RNA can also be detected, since it usually folds back onto itself and thus provides local base pairing for the ... Ethidium bromide is commonly used to detect nucleic acids in molecular biology laboratories. In the case of DNA this is usually ... Ethidium bromide is thought to act as a mutagen because it intercalates double stranded DNA (i.e., inserts itself between the ... It is added to running buffer and binds by intercalating between DNA base pairs. When the agarose gel is illuminated using UV ...
Isolated, purified, and recombinant nucleic acids and proteins corresponding to the human GC6 gene and its mRNA and protein ... "base-pairing" between nucleotides to form double-stranded complexes. A first oligonucleotide or polynucleotide is complementary ... The newly synthesized strand and its complementary nucleic acid strand form double-stranded molecules used in the succeeding ... The formation of a duplex nucleic acid from two single-stranded nucleic acids (such as an oligonucleotide probe to a target ...
... nucleic acid sequence. b) amplifying the multiplicity of oligonucleotides to provide a pool of amplified nucleic acids; and c) ... nucleic acid affinity ligands allowing the simultaneous selection and removal of a large number of preselected nucleic acids ... In general the methods involve the steps of a) providing a nucleic acid amplification template array comprising a surface to ... attaching the pool of nucleic acids to a solid support. ... Nucleic acid affinity matrices that bear a large number of ...
... which permit enhanced binding to nucleic add of pathogens. Higher psoralen binding levels and lower mutagenicity are described ... Psoralens can intercalate between the base pairs of double-stranded nucleic acids, forming covalent adducts to pyrimidine bases ... Its nucleic acid may be single stranded or double stranded, DNA or RNA. The photoactivating means comprises a photoactivation ... Its nucleic acid may be single stranded or double stranded, DNA or RNA. The photoactivating means comprises a photoactivation ...
As such, circulating miRNAs are attractive potential biomarkers and hold promise for the development of miRNA-based ... A class of exogenous double-stranded RNA molecules, 20-25 base pairs in length, similar to microRNAs, and used widely as a gene ... An exploration of nucleic acid liquid biopsy using a glucose meter. Chem. Sci. 9, 3517-3522 (2018). ... A technique used to quantify the absolute copies of nucleic acids directly. ...
... base pair mismatch include Methods to Increase the Sensitivity of High Resolution Melting Single Nucleotide Polymorphism ... Base Pair Mismatch: The presence of an uncomplimentary base in double-stranded DNA caused by spontaneous deamination of ... Multiple, sequential base pair mismatches lead to formation of heteroduplex DNA; (Nucleic acid heteroduplexes). Methods to ...
  • Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) and CRISPR-associated (Cas) systems in bacteria and archaea use RNA-guided nuclease activity to provide adaptive immunity against invading foreign nucleic acids. (nih.gov)
  • During the 1980s detailed x-ray crystallographic analyses of DNA became acknowledged as proof of the structural arrangement that had been described by Watson and Crick, including the Watson - Crick complementary base-pairing arrangements. (encyclopedia.com)
  • Yet, information about nucleic acid polymer properties is mainly derived from studies of ssDNA. (pnas.org)
  • 3. The nucleic acid-encapsulating polymer micelle complex according to Claim 1 or 2, wherein the single-stranded DNA is 2000 or more bases in length, and the double-stranded DNA is 2000 or more base pairs in length. (go.jp)
  • 4. The nucleic acid-encapsulating polymer micelle complex according to any one of Claims 1 to 3, wherein the average particle diameter thereof in an aqueous medium measured according to a dynamic light scattering method is 100 nm or less. (go.jp)
  • 5. The nucleic acid-encapsulating polymer micelle complex according to any one of Claims 1 to 4, wherein the DNA and the cationic polymer chain block bonded to the DNA due to an electrostatic interaction form a core portion, and the uncharged hydrophilic polymer chain block forms a shell portion. (go.jp)
  • 6. The nucleic acid-encapsulating polymer micelle complex according to Claim 5, wherein the average particle diameter of the core portion is 50 nm or less. (go.jp)
  • 7. The nucleic acid-encapsulating polymer micelle complex according to any one of Claims 1 to 6, wherein the complex is spherical. (go.jp)
  • 9. The nucleic acid-encapsulating polymer micelle complex according to any one of Claims 1 to 8, wherein at least a part of the block copolymer is mutually cross-linked. (go.jp)
  • 10. The nucleic acid-encapsulating polymer micelle complex according to any one of Claims 1 to 9, wherein a hydrophobic group is covalently bonded to a main chain or a side chain of the cationic polymer chain block. (go.jp)
  • 13. The method for producing a nucleic acid-encapsulating polymer micelle complex according to Claim 12, wherein the double-stranded DNA is 2000 or more base pairs in length. (go.jp)
  • Positions of hybridization of a target nucleic acid are determined by, e.g., epifluorescence microscopy. (patents.com)
  • Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) systems provide bacteria and archaea with adaptive immunity against viruses and plasmids by using CRISPR RNAs (crRNAs) to guide the silencing of invading nucleic acids. (sciencemag.org)
  • The CRISPR-Cas adaptive microbial immune system confers acquired resistance against invading nucleic acids. (springer.com)
  • If one or more of the DNA strands run in opposite direction, it is termed as an anti-parallel quadruplex, and can either be in a form of a lateral/edgewise, connecting adjacent anti-parallel strands, or a diagonal, joining two diagonally opposite strands. (wikipedia.org)
  • The faeA genes from Aspergillus niger and Aspergillus tubingensis encode ferulic acid esterases involved in degradation of complex cell wall polysaccharides," Applied and Environmental Microbiology, vol. 63, No. 12, Dec.1997 pp. 4638-4644, XP002203731. (patentgenius.com)
  • Devices and methods for carrying out an assay for the determination of nucleic acids are disclosed. (google.ca)
  • The methods involve introducing a sample suspected of containing a nucleic acid analyte into a device in accordance with the invention. (google.ca)
  • His research interests broadly encompass new synthetic methods, but with a particular focus on nucleic acids. (rsc.org)
  • She started her PhD work in Prof. Dennis Gillingham's group at the University of Basel in 2011, where she is developing new methods for the alkylation of nucleic acids. (rsc.org)
  • Recently a number of enantioselective processes for carbenoid-based N-H and O-H insertions have been developed, again expanding the potential applicability of these methods. (rsc.org)
  • Detection of DNA Base Mismatches Using DNA Intercalators Methods in Enzymology. (jove.com)
  • The films, compositions, collection devices, kits and methods can be used for collection of fingerprints for both image capture and nucleic acid extraction and analysis. (justia.com)