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Peptide Elongation Factor Tu: A protein found in bacteria and eukaryotic mitochondria which delivers aminoacyl-tRNA's to the A site of the ribosome. The aminoacyl-tRNA is first bound to a complex of elongation factor Tu containing a molecule of bound GTP. The resulting complex is then bound to the 70S initiation complex. Simultaneously the GTP is hydrolyzed and a Tu-GDP complex is released from the 70S ribosome. The Tu-GTP complex is regenerated from the Tu-GDP complex by the Ts elongation factor and GTP.Peptide Elongation Factor 1: Peptide elongation factor 1 is a multisubunit protein that is responsible for the GTP-dependent binding of aminoacyl-tRNAs to eukaryotic ribosomes. The alpha subunit (EF-1alpha) binds aminoacyl-tRNA and transfers it to the ribosome in a process linked to GTP hydrolysis. The beta and delta subunits (EF-1beta, EF-1delta) are involved in exchanging GDP for GTP. The gamma subunit (EF-1gamma) is a structural component.Peptide Elongation Factors: Protein factors uniquely required during the elongation phase of protein synthesis.GTP Phosphohydrolase-Linked Elongation Factors: Factors that utilize energy from the hydrolysis of GTP to GDP for peptide chain elongation. EC 3.6.1.-.Peptide Chain Elongation, Translational: A process of GENETIC TRANSLATION, when an amino acid is transferred from its cognate TRANSFER RNA to the lengthening chain of PEPTIDES.RNA, Transfer, Amino Acyl: Intermediates in protein biosynthesis. The compounds are formed from amino acids, ATP and transfer RNA, a reaction catalyzed by aminoacyl tRNA synthetase. They are key compounds in the genetic translation process.Peptide Elongation Factor 2: Peptide Elongation Factor 2 catalyzes the translocation of peptidyl-tRNA from the A site to the P site of eukaryotic ribosomes by a process linked to the hydrolysis of GTP to GDP.Peptide Elongation Factor G: Peptide Elongation Factor G catalyzes the translocation of peptidyl-tRNA from the A to the P site of bacterial ribosomes by a process linked to hydrolysis of GTP to GDP.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.Guanosine Triphosphate: Guanosine 5'-(tetrahydrogen triphosphate). A guanine nucleotide containing three phosphate groups esterified to the sugar moiety.Pyridones: Pyridine derivatives with one or more keto groups on the ring.RNA, Transfer, Phe: A transfer RNA which is specific for carrying phenylalanine to sites on the ribosomes in preparation for protein synthesis.Guanosine Diphosphate: A guanine nucleotide containing two phosphate groups esterified to the sugar moiety.Ribosomes: Multicomponent ribonucleoprotein structures found in the CYTOPLASM of all cells, and in MITOCHONDRIA, and PLASTIDS. They function in PROTEIN BIOSYNTHESIS via GENETIC TRANSLATION.Aurodox: Antibiotic obtained from a Streptomyces variant considered as possibly effective against Streptococcus pyogenes infections. It may promote growth in poultry.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.Peptide Biosynthesis: The production of PEPTIDES or PROTEINS by the constituents of a living organism. The biosynthesis of proteins on RIBOSOMES following an RNA template is termed translation (TRANSLATION, GENETIC). There are other, non-ribosomal peptide biosynthesis (PEPTIDE BIOSYNTHESIS, NUCLEIC ACID-INDEPENDENT) mechanisms carried out by PEPTIDE SYNTHASES and PEPTIDYLTRANSFERASES. Further modifications of peptide chains yield functional peptide and protein molecules.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.Transcriptional Elongation Factors: Transcription factors whose primary function is to regulate the rate in which RNA is transcribed.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.Guanine NucleotidesElongation Factor 2 Kinase: A monomeric calcium-calmodulin-dependent protein kinase subtype that specifically phosphorylates PEPTIDE ELONGATION FACTOR 2. The enzyme lacks a phosphorylatable activation domain that can respond to CALCIUM-CALMODULIN-DEPENDENT PROTEIN KINASE KINASE, however it is regulated by phosphorylation by PROTEIN KINASE A and through intramolecular autophosphorylation.Thermus thermophilus: A species of gram-negative, aerobic, rod-shaped bacteria found in hot springs of neutral to alkaline pH, as well as in hot-water heaters.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.Thermus: Gram-negative aerobic rods found in warm water (40-79 degrees C) such as hot springs, hot water tanks, and thermally polluted rivers.Tosylphenylalanyl Chloromethyl Ketone: An inhibitor of Serine Endopeptidases. Acts as alkylating agent and is known to interfere with the translation process.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.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.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.RNA, Transfer, Amino Acid-Specific: A group of transfer RNAs which are specific for carrying each one of the 20 amino acids to the ribosome in preparation for protein synthesis.Positive Transcriptional Elongation Factor B: A transcriptional elongation factor complex that is comprised of a heterodimer of CYCLIN-DEPENDENT KINASE 9 and one of several CYCLINS including TYPE T CYCLINS and cyclin K. It functions by phosphorylating the carboxy-terminal domain of RNA POLYMERASE II.Kinetics: The rate dynamics in chemical or physical systems.Bacterial Proteins: Proteins found in any species of bacterium.Euglena gracilis: A species of fresh-water, flagellated EUKARYOTES in the phylum EUGLENIDA.Peptide Fragments: Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.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).Phenylalanine: An essential aromatic amino acid that is a precursor of MELANIN; DOPAMINE; noradrenalin (NOREPINEPHRINE), and THYROXINE.Transfer RNA Aminoacylation: The conversion of uncharged TRANSFER RNA to AMINO ACYL TRNA.Hydrolysis: The process of cleaving a chemical compound by the addition of a molecule of water.Ribosomal Proteins: Proteins found in ribosomes. They are believed to have a catalytic function in reconstituting biologically active ribosomal subunits.RNA, Transfer, Ala: A transfer RNA which is specific for carrying alanine to sites on the ribosomes in preparation for protein synthesis.RNA, Transfer, Asn: A transfer RNA which is specific for carrying asparagine to sites on the ribosomes in preparation for protein synthesis.Peptides, Cyclic: Peptides whose amino and carboxy ends are linked together with a peptide bond forming a circular chain. Some of them are ANTI-INFECTIVE AGENTS. Some of them are biosynthesized non-ribosomally (PEPTIDE BIOSYNTHESIS, NON-RIBOSOMAL).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.RNA, Transfer, Thr: A transfer RNA which is specific for carrying threonine to sites on the ribosomes in preparation for protein synthesis.Trypsin: A serine endopeptidase that is formed from TRYPSINOGEN in the pancreas. It is converted into its active form by ENTEROPEPTIDASE in the small intestine. It catalyzes hydrolysis of the carboxyl group of either arginine or lysine. EC 3.4.21.4.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.RNA Polymerase II: A DNA-dependent RNA polymerase present in bacterial, plant, and animal cells. It functions in the nucleoplasmic structure and transcribes DNA into RNA. It has different requirements for cations and salt than RNA polymerase I and is strongly inhibited by alpha-amanitin. EC 2.7.7.6.Anti-Bacterial Agents: Substances that reduce the growth or reproduction of BACTERIA.Transcription Factors, General: Transcription factors that form transcription initiation complexes on DNA, bind to specific DNA-DIRECTED RNA POLYMERASES and are required to initiate transcription. Although their binding may be localized to distinct sequence and structural motifs within the DNA they are considered non-specific with regard to the specific gene being transcribed.RNA, Bacterial: Ribonucleic acid in bacteria having regulatory and catalytic roles as well as involvement in protein synthesis.Nucleic Acid Conformation: The spatial arrangement of the atoms of a nucleic acid or polynucleotide that results in its characteristic 3-dimensional shape.RNA, Transfer, Asp: A transfer RNA which is specific for carrying aspartic acid to sites on the ribosomes in preparation for protein synthesis.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.Fusidic Acid: An antibiotic isolated from the fermentation broth of Fusidium coccineum. (From Merck Index, 11th ed). It acts by inhibiting translocation during protein synthesis.Guanosine Tetraphosphate: Guanosine 5'-diphosphate 2'(3')-diphosphate. A guanine nucleotide containing four phosphate groups. Two phosphate groups are esterified to the sugar moiety in the 5' position and the other two in the 2' or 3' position. This nucleotide serves as a messenger to turn off the synthesis of ribosomal RNA when amino acids are not available for protein synthesis. Synonym: magic spot I.Codon: A set of three nucleotides in a protein coding sequence that specifies individual amino acids or a termination signal (CODON, TERMINATOR). Most codons are universal, but some organisms do not produce the transfer RNAs (RNA, TRANSFER) complementary to all codons. These codons are referred to as unassigned codons (CODONS, NONSENSE).Amino Acyl-tRNA Synthetases: A subclass of enzymes that aminoacylate AMINO ACID-SPECIFIC TRANSFER RNA with their corresponding AMINO ACIDS.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Genes, Bacterial: The functional hereditary units of BACTERIA.Aminoglycosides: Glycosylated compounds in which there is an amino substituent on the glycoside. Some of them are clinically important ANTIBIOTICS.Geobacillus stearothermophilus: A species of GRAM-POSITIVE ENDOSPORE-FORMING BACTERIA in the family BACILLACEAE, found in soil, hot springs, Arctic waters, ocean sediments, and spoiled food products.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.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.Macromolecular Substances: Compounds and molecular complexes that consist of very large numbers of atoms and are generally over 500 kDa in size. In biological systems macromolecular substances usually can be visualized using ELECTRON MICROSCOPY and are distinguished from ORGANELLES by the lack of a membrane structure.Guanylyl Imidodiphosphate: A non-hydrolyzable analog of GTP, in which the oxygen atom bridging the beta to the gamma phosphate is replaced by a nitrogen atom. It binds tightly to G-protein in the presence of Mg2+. The nucleotide is a potent stimulator of ADENYLYL CYCLASES.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.Peptide Library: A collection of cloned peptides, or chemically synthesized peptides, frequently consisting of all possible combinations of amino acids making up an n-amino acid peptide.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.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.RNA, Transfer, Met: A transfer RNA which is specific for carrying methionine to sites on the ribosomes. During initiation of protein synthesis, tRNA(f)Met in prokaryotic cells and tRNA(i)Met in eukaryotic cells binds to the start codon (CODON, INITIATOR).Amino Acids: Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.Histidine: An essential amino acid that is required for the production of HISTAMINE.Recombinant Proteins: Proteins prepared by recombinant DNA technology.