An enzyme that catalyzes the conversion of linear RNA to a circular form by the transfer of the 5'-phosphate to the 3'-hydroxyl terminus. It also catalyzes the covalent joining of two polyribonucleotides in phosphodiester linkage. EC 6.5.1.3.
Catalyze the joining of preformed ribonucleotides or deoxyribonucleotides in phosphodiester linkage during genetic processes. EC 6.5.1.
An enzyme that catalyzes the transfer of a phosphate group to the 5'-terminal hydroxyl groups of DNA and RNA. EC 2.7.1.78.
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.
A subclass of enzymes that aminoacylate AMINO ACID-SPECIFIC TRANSFER RNA with their corresponding AMINO ACIDS.
The ultimate exclusion of nonsense sequences or intervening sequences (introns) before the final RNA transcript is sent to the cytoplasm.
Enzymes of the transferase class that catalyze the conversion of L-aspartate and 2-ketoglutarate to oxaloacetate and L-glutamate. EC 2.6.1.1.
An enzyme that catalyzes the conversion of carbamoyl phosphate and L-aspartate to yield orthophosphate and N-carbamoyl-L-aspartate. (From Enzyme Nomenclature, 1992) EC 2.1.3.2.
A large superfamily of transcription factors that contain a region rich in BASIC AMINO ACID residues followed by a LEUCINE ZIPPER domain.
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.
Enzymes that catalyze the S-adenosyl-L-methionine-dependent methylation of ribonucleotide bases within a transfer RNA molecule. EC 2.1.1.
One of the non-essential amino acids commonly occurring in the L-form. It is found in animals and plants, especially in sugar cane and sugar beets. It may be a neurotransmitter.
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.
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.
A diverse class of enzymes that interact with UBIQUITIN-CONJUGATING ENZYMES and ubiquitination-specific protein substrates. Each member of this enzyme group has its own distinct specificity for a substrate and ubiquitin-conjugating enzyme. Ubiquitin-protein ligases exist as both monomeric proteins multiprotein complexes.
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.
The sequential set of three nucleotides in TRANSFER RNA that interacts with its complement in MESSENGER RNA, the CODON, during translation in the ribosome.
Poly(deoxyribonucleotide):poly(deoxyribonucleotide)ligases. Enzymes that catalyze the joining of preformed deoxyribonucleotides in phosphodiester linkage during genetic processes during repair of a single-stranded break in duplex DNA. The class includes both EC 6.5.1.1 (ATP) and EC 6.5.1.2 (NAD).
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.
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.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
A transfer RNA which is specific for carrying serine to sites on the ribosomes in preparation for protein synthesis.
The spatial arrangement of the atoms of a nucleic acid or polynucleotide that results in its characteristic 3-dimensional shape.
An enzyme that catalyzes the formation of beta-aspartyl phosphate from aspartic acid and ATP. Threonine serves as an allosteric regulator of this enzyme to control the biosynthetic pathway from aspartic acid to threonine. EC 2.7.2.4.
The act of ligating UBIQUITINS to PROTEINS to form ubiquitin-protein ligase complexes to label proteins for transport to the PROTEASOME ENDOPEPTIDASE COMPLEX where proteolysis occurs.
A transfer RNA which is specific for carrying phenylalanine to sites on the ribosomes in preparation for protein synthesis.
Complexes of enzymes that catalyze the covalent attachment of UBIQUITIN to other proteins by forming a peptide bond between the C-terminal GLYCINE of UBIQUITIN and the alpha-amino groups of LYSINE residues in the protein. The complexes play an important role in mediating the selective-degradation of short-lived and abnormal proteins. The complex of enzymes can be broken down into three components that involve activation of ubiquitin (UBIQUITIN-ACTIVATING ENZYMES), conjugation of ubiquitin to the ligase complex (UBIQUITIN-CONJUGATING ENZYMES), and ligation of ubiquitin to the substrate protein (UBIQUITIN-PROTEIN LIGASES).
A transfer RNA which is specific for carrying tryptophan to sites on the ribosomes in preparation for protein synthesis.
A transfer RNA which is specific for carrying aspartic acid to sites on the ribosomes in preparation for protein synthesis.
A transfer RNA which is specific for carrying arginine to sites on the ribosomes in preparation for protein synthesis.
A class of enzymes that catalyze the formation of a bond between two substrate molecules, coupled with the hydrolysis of a pyrophosphate bond in ATP or a similar energy donor. (Dorland, 28th ed) EC 6.
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.
A family of structurally related proteins that were originally discovered for their role in cell-cycle regulation in CAENORHABDITIS ELEGANS. They play important roles in regulation of the CELL CYCLE and as components of UBIQUITIN-PROTEIN LIGASES.
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).
A transfer RNA which is specific for carrying glycine to sites on the ribosomes in preparation for protein synthesis.
A transfer RNA which is specific for carrying isoleucine to sites on the ribosomes in preparation for protein synthesis.
A highly conserved 76-amino acid peptide universally found in eukaryotic cells that functions as a marker for intracellular PROTEIN TRANSPORT and degradation. Ubiquitin becomes activated through a series of complicated steps and forms an isopeptide bond to lysine residues of specific proteins within the cell. These "ubiquitinated" proteins can be recognized and degraded by proteosomes or be transported to specific compartments within the cell.
The rate dynamics in chemical or physical systems.
A transfer RNA which is specific for carrying alanine to sites on the ribosomes in preparation for protein synthesis.
One of the enzymes active in the gamma-glutamyl cycle. It catalyzes the synthesis of gamma-glutamylcysteine from glutamate and cysteine in the presence of ATP with the formation of ADP and orthophosphate. EC 6.3.2.2.
A transfer RNA which is specific for carrying glutamic acid to sites on the ribosomes in preparation for protein synthesis.
A transfer RNA which is specific for carrying valine to sites on the ribosomes in preparation for protein synthesis.
An enzyme that catalyzes the conversion of L-alanine and 2-oxoglutarate to pyruvate and L-glutamate. (From Enzyme Nomenclature, 1992) EC 2.6.1.2.
An enzyme that catalyzes the conversion of aspartic acid to ammonia and fumaric acid in plants and some microorganisms. EC 4.3.1.1.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
A transfer RNA which is specific for carrying glutamine to sites on the ribosomes in preparation for protein synthesis.
A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.
A transfer RNA which is specific for carrying proline to sites on the ribosomes in preparation for protein synthesis.
A transfer RNA which is specific for carrying histidine to sites on the ribosomes in preparation for protein synthesis.
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.
Cell surface proteins that bind amino acids and trigger changes which influence the behavior of cells. Glutamate receptors are the most common receptors for fast excitatory synaptic transmission in the vertebrate central nervous system, and GAMMA-AMINOBUTYRIC ACID and glycine receptors are the most common receptors for fast inhibition.
Ribonucleic acid in bacteria having regulatory and catalytic roles as well as involvement in protein synthesis.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
Derivatives of GLUTAMIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the 2-aminopentanedioic acid structure.
A DNA amplification technique based upon the ligation of OLIGONUCLEOTIDE PROBES. The probes are designed to exactly match two adjacent sequences of a specific target DNA. The chain reaction is repeated in three steps in the presence of excess probe: (1) heat denaturation of double-stranded DNA, (2) annealing of probes to target DNA, and (3) joining of the probes by thermostable DNA ligase. After the reaction is repeated for 20-30 cycles the production of ligated probe is measured.
A subset of ubiquitin protein ligases that are formed by the association of a SKP DOMAIN PROTEIN, a CULLIN DOMAIN PROTEIN and a F-BOX DOMAIN PROTEIN.
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.
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).
An aspartate aminotransferase found in MITOCHONDRIA.
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.
A family of proteins that share the F-BOX MOTIF and are involved in protein-protein interactions. They play an important role in process of protein ubiquition by associating with a variety of substrates and then associating into SCF UBIQUITIN LIGASE complexes. They are held in the ubiquitin-ligase complex via binding to SKP DOMAIN PROTEINS.
A transfer RNA which is specific for carrying threonine to sites on the ribosomes in preparation for protein synthesis.
A simple organophosphorus compound that inhibits DNA polymerase, especially in viruses and is used as an antiviral agent.
A class of enzymes that form a thioester bond to UBIQUITIN with the assistance of UBIQUITIN-ACTIVATING ENZYMES. They transfer ubiquitin to the LYSINE of a substrate protein with the assistance of UBIQUITIN-PROTEIN LIGASES.
Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.
A reaction that introduces an aminoacyl group to a molecule. TRANSFER RNA AMINOACYLATION is the first step in GENETIC TRANSLATION.
An enzyme that activates serine with its specific transfer RNA. EC 6.1.1.11.
The monoanhydride of carbamic acid with PHOSPHORIC ACID. It is an important intermediate metabolite and is synthesized enzymatically by CARBAMYL-PHOSPHATE SYNTHASE (AMMONIA) and CARBAMOYL-PHOSPHATE SYNTHASE (GLUTAMINE-HYDROLYZING).
A zinc-binding domain defined by the sequence Cysteine-X2-Cysteine-X(9-39)-Cysteine-X(l-3)-His-X(2-3)-Cysteine-X2-Cysteine -X(4-48)-Cysteine-X2-Cysteine, where X is any amino acid. The RING finger motif binds two atoms of zinc, with each zinc atom ligated tetrahedrally by either four cysteines or three cysteines and a histidine. The motif also forms into a unitary structure with a central cross-brace region and is found in many proteins that are involved in protein-protein interactions. The acronym RING stands for Really Interesting New Gene.
Ribonucleic acid in fungi having regulatory and catalytic roles as well as involvement in protein synthesis.
Cytidine 5'-(tetrahydrogen triphosphate). A cytosine nucleotide containing three phosphate groups esterified to the sugar moiety.
A photoactivable URIDINE analog that is used as an affinity label.
A transfer RNA which is specific for carrying cysteine to sites on the ribosomes in preparation for protein synthesis.
The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.
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.
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
A non-essential amino acid naturally occurring in the L-form. Glutamic acid is the most common excitatory neurotransmitter in the CENTRAL NERVOUS SYSTEM.
An enzyme that, in the course of pyrimidine biosynthesis, catalyzes ring closure by removal of water from N-carbamoylaspartate to yield dihydro-orotic acid. EC 3.5.2.3.
An enzyme that activates aspartic acid with its specific transfer RNA. EC 6.1.1.12.
The biosynthesis of PEPTIDES and PROTEINS on RIBOSOMES, directed by MESSENGER RNA, via TRANSFER RNA that is charged with standard proteinogenic AMINO ACIDS.
A non-essential amino acid present abundantly throughout the body and is involved in many metabolic processes. It is synthesized from GLUTAMIC ACID and AMMONIA. It is the principal carrier of NITROGEN in the body and is an important energy source for many cells.
Mutation process that restores the wild-type PHENOTYPE in an organism possessing a mutationally altered GENOTYPE. The second "suppressor" mutation may be on a different gene, on the same gene but located at a distance from the site of the primary mutation, or in extrachromosomal genes (EXTRACHROMOSOMAL INHERITANCE).
A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.
A large multisubunit complex that plays an important role in the degradation of most of the cytosolic and nuclear proteins in eukaryotic cells. It contains a 700-kDa catalytic sub-complex and two 700-kDa regulatory sub-complexes. The complex digests ubiquitinated proteins and protein activated via ornithine decarboxylase antizyme.
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).
A non-essential amino acid that occurs in high levels in its free state in plasma. It is produced from pyruvate by transamination. It is involved in sugar and acid metabolism, increases IMMUNITY, and provides energy for muscle tissue, BRAIN, and the CENTRAL NERVOUS SYSTEM.
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.
Multicomponent ribonucleoprotein structures found in the CYTOPLASM of all cells, and in MITOCHONDRIA, and PLASTIDS. They function in PROTEIN BIOSYNTHESIS via GENETIC TRANSLATION.
A transfer RNA which is specific for carrying asparagine to sites on the ribosomes in preparation for protein synthesis.
The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.
An essential amino acid. It is often added to animal feed.
Established cell cultures that have the potential to propagate indefinitely.
This is the active form of VITAMIN B 6 serving as a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid. During transamination of amino acids, pyridoxal phosphate is transiently converted into pyridoxamine phosphate (PYRIDOXAMINE).
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.
The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Post-transcriptional biological modification of messenger, transfer, or ribosomal RNAs or their precursors. It includes cleavage, methylation, thiolation, isopentenylation, pseudouridine formation, conformational changes, and association with ribosomal protein.
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.
Proteins found in any species of bacterium.

Synthesis of aspartyl-tRNA(Asp) in Escherichia coli--a snapshot of the second step. (1/130)

The 2.4 A crystal structure of the Escherichia coli aspartyl-tRNA synthetase (AspRS)-tRNA(Asp)-aspartyl-adenylate complex shows the two substrates poised for the transfer of the aspartic acid moiety from the adenylate to the 3'-hydroxyl of the terminal adenosine of the tRNA. A general molecular mechanism is proposed for the second step of the aspartylation reaction that accounts for the observed conformational changes, notably in the active site pocket. The stabilization of the transition state is mediated essentially by two amino acids: the class II invariant arginine of motif 2 and the eubacterial-specific Gln231, which in eukaryotes and archaea is replaced by a structurally non-homologous serine. Two archetypal RNA-protein modes of interactions are observed: the anticodon stem-loop, including the wobble base Q, binds to the N-terminal beta-barrel domain through direct protein-RNA interactions, while the binding of the acceptor stem involves both direct and water-mediated hydrogen bonds in an original recognition scheme.  (+info)

A missense mutation in the nuclear gene coding for the mitochondrial aspartyl-tRNA synthetase suppresses a mitochondrial tRNA(Asp) mutation. (2/130)

The nuclear suppressor allele NSM3 in strain FF1210-6C/170-E22 (E22), which suppresses a mutation of the yeast mitochondrial tRNA(Asp)gene in Saccharomyces cerevisiae, was cloned and identified. To isolate the NSM3 allele, a genomic DNA library using the vector YEp13 was constructed from strain E22. Nine YEp13 recombinant plasmids were isolated and shown to suppress the mutation in the mitochondrial tRNA(Asp)gene. These nine plasmids carry a common 4. 5-kb chromosomal DNA fragment which contains an open reading frame coding for yeast mitochondrial aspartyl-tRNA synthetase (AspRS) on the basis of its sequence identity to the MSD1 gene. The comparison of NSM3 DNA sequences between the suppressor and the wild-type version, cloned from the parental strain FF1210-6C/170, revealed a G to A transition that causes the replacement of amino acid serine (AGU) by an asparagine (AAU) at position 388. In experiments switching restriction fragments between the wild type and suppressor versions of the NSM3 gene, the rescue of respiratory deficiency was demonstrated only when the substitution was present in the construct. We conclude that the base substitution causes the respiratory rescue and discuss the possible mechanism as one which enhances interaction between the mutated tRNA(Asp)and the suppressor version of AspRS.  (+info)

A domain in the N-terminal extension of class IIb eukaryotic aminoacyl-tRNA synthetases is important for tRNA binding. (3/130)

Cytoplasmic aspartyl-tRNA synthetase (AspRS) from Saccharomyces cerevisiae is a homodimer of 64 kDa subunits. Previous studies have emphasized the high sensitivity of the N-terminal region to proteolytic cleavage, leading to truncated species that have lost the first 20-70 residues but that retain enzymatic activity and dimeric structure. In this work, we demonstrate that the N-terminal extension in yeast AspRS participates in tRNA binding and we generalize this finding to eukaryotic class IIb aminoacyl-tRNA synthetases. By gel retardation studies and footprinting experiments on yeast tRNA(Asp), we show that the extension, connected to the anticodon-binding module of the synthetase, contacts tRNA on the minor groove side of its anticodon stem. Sequence comparison of eukaryotic class IIb synthetases identifies a lysine-rich 11 residue sequence ((29)LSKKALKKLQK(39) in yeast AspRS with the consensus xSKxxLKKxxK in class IIb synthetases) that is important for this binding. Direct proof of the role of this sequence comes from a mutagenesis analysis and from binding studies using the isolated peptide.  (+info)

Metabolism of D-aminoacyl-tRNAs in Escherichia coli and Saccharomyces cerevisiae cells. (4/130)

In Escherichia coli, tyrosyl-tRNA synthetase is known to esterify tRNA(Tyr) with tyrosine. Resulting d-Tyr-tRNA(Tyr) can be hydrolyzed by a d-Tyr-tRNA(Tyr) deacylase. By monitoring E. coli growth in liquid medium, we systematically searched for other d-amino acids, the toxicity of which might be exacerbated by the inactivation of the gene encoding d-Tyr-tRNA(Tyr) deacylase. In addition to the already documented case of d-tyrosine, positive responses were obtained with d-tryptophan, d-aspartate, d-serine, and d-glutamine. In agreement with this observation, production of d-Asp-tRNA(Asp) and d-Trp-tRNA(Trp) by aspartyl-tRNA synthetase and tryptophanyl-tRNA synthetase, respectively, was established in vitro. Furthermore, the two d-aminoacylated tRNAs behaved as substrates of purified E. coli d-Tyr-tRNA(Tyr) deacylase. These results indicate that an unexpected high number of d-amino acids can impair the bacterium growth through the accumulation of d-aminoacyl-tRNA molecules and that d-Tyr-tRNA(Tyr) deacylase has a specificity broad enough to recycle any of these molecules. The same strategy of screening was applied using Saccharomyces cerevisiae, the tyrosyl-tRNA synthetase of which also produces d-Tyr-tRNA(Tyr), and which, like E. coli, possesses a d-Tyr-tRNA(Tyr) deacylase activity. In this case, inhibition of growth by the various 19 d-amino acids was followed on solid medium. Two isogenic strains containing or not the deacylase were compared. Toxic effects of d-tyrosine and d-leucine were reinforced upon deprivation of the deacylase. This observation suggests that, in yeast, at least two d-amino acids succeed in being transferred onto tRNAs and that, like in E. coli, the resulting two d-aminoacyl-tRNAs are substrates of a same d-aminoacyl-tRNA deacylase.  (+info)

Magnesium ion-mediated binding to tRNA by an amino-terminal peptide of a class II tRNA synthetase. (5/130)

Aspartyl-tRNA synthetase is a class II tRNA synthetase and occurs in a multisynthetase complex in mammalian cells. Human Asp-tRNA synthetase contains a short 32-residue amino-terminal extension that can control the release of charged tRNA and its direct transfer to elongation factor 1 alpha; however, whether the extension binds to tRNA directly or interacts with the synthetase active site is not known. Full-length human AspRS, but not amino-terminal 32 residue-deleted, fully active AspRS, was found to bind to noncognate tRNA(fMet) in the presence of Mg(2+). Synthetic amino-terminal peptides bound similarly to tRNA(fMet), whereas little or no binding of polynucleotides, poly(dA-dT), or polyphosphate to the peptides was found. The apparent binding constants to tRNA by the peptide increased with increasing concentrations of Mg(2+), suggesting Mg(2+) mediates the binding as a new mode of RNA.peptide interactions. The binding of tRNA(fMet) to amino-terminal peptides was also observed using fluorescence-labeled tRNAs and circular dichroism. These results suggest that a small peptide can bind to tRNA selectively and that evolution of class II tRNA synthetases may involve structural changes of amino-terminal extensions for enhanced selective binding of tRNA.  (+info)

Human anti-asparaginyl-tRNA synthetase autoantibodies (anti-KS) increase the affinity of the enzyme for its tRNA substrate. (6/130)

Autoantibodies directed against specific human aminoacyl-tRNA synthetases have been associated with a clinical picture including myositis, arthritis, interstitial lung disease and other features that has been referred to as the "anti-synthetase syndrome". Anti-asparaginyl-tRNA synthetase autoantibodies (anti-KS), the most recently described anti-synthetase autoantibodies, are directed against human cytosolic asparaginyl-tRNA synthetase and neutralize specifically its activity. Here we show that these antibodies recognize two epitopes on the human enzyme, an N-terminal epitope reactive in immunoblot experiments and a heat-labile epitope in the catalytic domain. In contrast to the well studied anti-Jo-1 autoantibodies anti-KS when bound to the synthetase increase the affinity of the synthetase for its tRNA substrate and prevent aminoacylation without interfering with the amino acid activation step.  (+info)

A dual-specific Glu-tRNA(Gln) and Asp-tRNA(Asn) amidotransferase is involved in decoding glutamine and asparagine codons in Acidithiobacillus ferrooxidans. (7/130)

The gatC, gatA and gatB genes encoding the three subunits of glutamyl-tRNA(Gln) amidotransferase from Acidithiobacillus ferrooxidans, an acidophilic bacterium used in bioleaching of minerals, have been cloned and expressed in Escherichia coli. As in Bacillus subtilis the three gat genes are organized in an operon-like structure in A. ferrooxidans. The heterologously overexpressed enzyme converts Glu-tRNA(Gln) to Gln-tRNA(Gln) and Asp-tRNA(Asn) to Asn-tRNA(Asn). Biochemical analysis revealed that neither glutaminyl-tRNA synthetase nor asparaginyl-tRNA synthetase is present in A. ferrooxidans, but that glutamyl-tRNA synthetase and aspartyl-tRNA synthetase enzymes are present in the organism. These data suggest that the transamidation pathway is responsible for the formation of Gln-tRNA and Asn-tRNA in A. ferrooxidans.  (+info)

The structure of an AspRS-tRNA(Asp) complex reveals a tRNA-dependent control mechanism. (8/130)

The 2.6 A resolution crystal structure of an inactive complex between yeast tRNA(Asp) and Escherichia coli aspartyl-tRNA synthetase reveals the molecular details of a tRNA-induced mechanism that controls the specificity of the reaction. The dimer is asymmetric, with only one of the two bound tRNAs entering the active site cleft of its subunit. However, the flipping loop, which controls the proper positioning of the amino acid substrate, acts as a lid and prevents the correct positioning of the terminal adenosine. The structure suggests that the acceptor stem regulates the loop movement through sugar phosphate backbone- protein interactions. Solution and cellular studies on mutant tRNAs confirm the crucial role of the tRNA three-dimensional structure versus a specific recognition of bases in the control mechanism.  (+info)

Polynucleotide ligases are enzymes that catalyze the formation of phosphodiester bonds between the 3'-hydroxyl and 5'-phosphate ends of two adjacent nucleotides in a polynucleotide chain, such as DNA. These enzymes play a crucial role in the repair and replication of DNA, by sealing breaks or gaps in the sugar-phosphate backbone of the DNA molecule. They are essential for maintaining genomic integrity and stability, and have been widely used in molecular biology research and biotechnological applications, including DNA sequencing, cloning, and genetic engineering. Polynucleotide ligases can be found in various organisms, from bacteria to humans, and they typically require ATP or NAD+ as a cofactor for the ligation reaction.

Polynucleotide 5'-Hydroxyl-Kinase (PNK) is an enzyme that catalyzes the addition of a phosphate group to the 5'-hydroxyl end of a polynucleotide strand, such as DNA or RNA. This enzyme plays a crucial role in the repair and maintenance of DNA ends during various cellular processes, including DNA replication, recombination, and repair.

PNK has two distinct activities: 5'-kinase activity and 3'-phosphatase activity. The 5'-kinase activity adds a phosphate group to the 5'-hydroxyl end of a polynucleotide strand, while the 3'-phosphatase activity removes a phosphate group from the 3'-end of a strand. These activities enable PNK to process and repair DNA ends with missing or damaged phosphate groups, ensuring their proper alignment and ligation during DNA repair and recombination.

PNK is involved in several essential cellular pathways, including base excision repair (BER), nucleotide excision repair (NER), and double-strand break (DSB) repair. Dysregulation or mutations in PNK can lead to genomic instability and contribute to the development of various diseases, such as cancer and neurodegenerative disorders.

Transfer RNA (tRNA) is a type of RNA molecule that plays a crucial role in protein synthesis, the process by which cells create proteins. In protein synthesis, tRNAs serve as adaptors, translating the genetic code present in messenger RNA (mRNA) into the corresponding amino acids required to build a protein.

Each tRNA molecule has a distinct structure, consisting of approximately 70-90 nucleotides arranged in a cloverleaf shape with several loops and stems. The most important feature of a tRNA is its anticodon, a sequence of three nucleotides located in one of the loops. This anticodon base-pairs with a complementary codon on the mRNA during translation, ensuring that the correct amino acid is added to the growing polypeptide chain.

Before tRNAs can participate in protein synthesis, they must be charged with their specific amino acids through an enzymatic process involving aminoacyl-tRNA synthetases. These enzymes recognize and bind to both the tRNA and its corresponding amino acid, forming a covalent bond between them. Once charged, the aminoacyl-tRNA complex is ready to engage in translation and contribute to protein formation.

In summary, transfer RNA (tRNA) is a small RNA molecule that facilitates protein synthesis by translating genetic information from messenger RNA into specific amino acids, ultimately leading to the creation of functional proteins within cells.

Aminoacyl-tRNA synthetases (also known as aminoacyl-tRNA ligases) are a group of enzymes that play a crucial role in protein synthesis. They are responsible for attaching specific amino acids to their corresponding transfer RNAs (tRNAs), creating aminoacyl-tRNA complexes. These complexes are then used in the translation process to construct proteins according to the genetic code.

Each aminoacyl-tRNA synthetase is specific to a particular amino acid, and there are 20 different synthetases in total, one for each of the standard amino acids. The enzymes catalyze the reaction between an amino acid and ATP to form an aminoacyl-AMP intermediate, which then reacts with the appropriate tRNA to create the aminoacyl-tRNA complex. This two-step process ensures the fidelity of the translation process by preventing mismatching of amino acids with their corresponding tRNAs.

Defects in aminoacyl-tRNA synthetases can lead to various genetic disorders and diseases, such as Charcot-Marie-Tooth disease type 2D, distal spinal muscular atrophy, and leukoencephalopathy with brainstem and spinal cord involvement and lactate acidosis (LBSL).

RNA splicing is a post-transcriptional modification process in which the non-coding sequences (introns) are removed and the coding sequences (exons) are joined together in a messenger RNA (mRNA) molecule. This results in a continuous mRNA sequence that can be translated into a single protein. Alternative splicing, where different combinations of exons are included or excluded, allows for the creation of multiple proteins from a single gene.

Aspartate aminotransferases (ASTs) are a group of enzymes found in various tissues throughout the body, including the heart, liver, and muscles. They play a crucial role in the metabolic process of transferring amino groups between different molecules.

In medical terms, AST is often used as a blood test to measure the level of this enzyme in the serum. Elevated levels of AST can indicate damage or injury to tissues that contain this enzyme, such as the liver or heart. For example, liver disease, including hepatitis and cirrhosis, can cause elevated AST levels due to damage to liver cells. Similarly, heart attacks can also result in increased AST levels due to damage to heart muscle tissue.

It is important to note that an AST test alone cannot diagnose a specific medical condition, but it can provide valuable information when used in conjunction with other diagnostic tests and clinical evaluation.

Aspartate carbamoyltransferase (ACT) is a crucial enzyme in the urea cycle, which is the biochemical pathway responsible for the elimination of excess nitrogen waste from the body. This enzyme catalyzes the second step of the urea cycle, where it facilitates the transfer of a carbamoyl group from carbamoyl phosphate to aspartic acid, forming N-acetylglutamic semialdehyde and releasing phosphate in the process.

The reaction catalyzed by aspartate carbamoyltransferase is as follows:

Carbamoyl phosphate + L-aspartate → N-acetylglutamic semialdehyde + P\_i + CO\_2

This enzyme plays a critical role in maintaining nitrogen balance and preventing the accumulation of toxic levels of ammonia in the body. Deficiencies or mutations in aspartate carbamoyltransferase can lead to serious metabolic disorders, such as citrullinemia and hyperammonemia, which can have severe neurological consequences if left untreated.

Basic-leucine zipper (bZIP) transcription factors are a family of transcriptional regulatory proteins characterized by the presence of a basic region and a leucine zipper motif. The basic region, which is rich in basic amino acids such as lysine and arginine, is responsible for DNA binding, while the leucine zipper motif mediates protein-protein interactions and dimerization.

BZIP transcription factors play important roles in various cellular processes, including gene expression regulation, cell growth, differentiation, and stress response. They bind to specific DNA sequences called AP-1 sites, which are often found in the promoter regions of target genes. BZIP transcription factors can form homodimers or heterodimers with other bZIP proteins, allowing for combinatorial control of gene expression.

Examples of bZIP transcription factors include c-Jun, c-Fos, ATF (activating transcription factor), and CREB (cAMP response element-binding protein). Dysregulation of bZIP transcription factors has been implicated in various diseases, including cancer, inflammation, and neurodegenerative disorders.

"Saccharomyces cerevisiae" is not typically considered a medical term, but it is a scientific name used in the field of microbiology. It refers to a species of yeast that is commonly used in various industrial processes, such as baking and brewing. It's also widely used in scientific research due to its genetic tractability and eukaryotic cellular organization.

However, it does have some relevance to medical fields like medicine and nutrition. For example, certain strains of S. cerevisiae are used as probiotics, which can provide health benefits when consumed. They may help support gut health, enhance the immune system, and even assist in the digestion of certain nutrients.

In summary, "Saccharomyces cerevisiae" is a species of yeast with various industrial and potential medical applications.

tRNA (transfer RNA) methyltransferases are a group of enzymes that catalyze the transfer of a methyl group (-CH3) to specific positions on the tRNA molecule. These enzymes play a crucial role in modifying and regulating tRNA function, stability, and interaction with other components of the translation machinery during protein synthesis.

The addition of methyl groups to tRNAs can occur at various sites, including the base moieties of nucleotides within the anticodon loop, the TψC loop, and the variable region. These modifications help maintain the structural integrity of tRNA molecules, enhance their ability to recognize specific codons during translation, and protect them from degradation by cellular nucleases.

tRNA methyltransferases are classified based on the type of methylation they catalyze:

1. N1-methyladenosine (m1A) methyltransferases: These enzymes add a methyl group to the N1 position of adenosine residues in tRNAs. An example is TRMT6/TRMT61A, which methylates adenosines at position 58 in human tRNAs.
2. N3-methylcytosine (m3C) methyltransferases: These enzymes add a methyl group to the N3 position of cytosine residues in tRNAs. An example is Dnmt2, which methylates cytosines at position 38 in various organisms.
3. N7-methylguanosine (m7G) methyltransferases: These enzymes add a methyl group to the N7 position of guanosine residues in tRNAs, primarily at position 46 within the TψC loop. An example is Trm8/Trm82, which catalyzes this modification in yeast and humans.
4. 2'-O-methylated nucleotides (Nm) methyltransferases: These enzymes add a methyl group to the 2'-hydroxyl group of ribose sugars in tRNAs, which can occur at various positions throughout the molecule. An example is FTSJ1, which methylates uridines at position 8 in human tRNAs.
5. Pseudouridine (Ψ) synthases: Although not technically methyltransferases, pseudouridine synthases catalyze the isomerization of uridine to pseudouridine, which can enhance tRNA stability and function. An example is Dyskerin (DKC1), which introduces Ψ at various positions in human tRNAs.

These enzymes play crucial roles in modifying tRNAs, ensuring proper folding, stability, and function during translation. Defects in these enzymes can lead to various diseases, including neurological disorders, cancer, and premature aging.

Aspartic acid is an α-amino acid with the chemical formula HO2CCH(NH2)CO2H. It is one of the twenty standard amino acids, and it is a polar, negatively charged, and hydrophilic amino acid. In proteins, aspartic acid usually occurs in its ionized form, aspartate, which has a single negative charge.

Aspartic acid plays important roles in various biological processes, including metabolism, neurotransmitter synthesis, and energy production. It is also a key component of many enzymes and proteins, where it often contributes to the formation of ionic bonds and helps stabilize protein structure.

In addition to its role as a building block of proteins, aspartic acid is also used in the synthesis of other important biological molecules, such as nucleotides, which are the building blocks of DNA and RNA. It is also a component of the dipeptide aspartame, an artificial sweetener that is widely used in food and beverages.

Like other amino acids, aspartic acid is essential for human health, but it cannot be synthesized by the body and must be obtained through the diet. Foods that are rich in aspartic acid include meat, poultry, fish, dairy products, eggs, legumes, and some fruits and vegetables.

Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.

'Escherichia coli' (E. coli) is a type of gram-negative, facultatively anaerobic, rod-shaped bacterium that commonly inhabits the intestinal tract of humans and warm-blooded animals. It is a member of the family Enterobacteriaceae and one of the most well-studied prokaryotic model organisms in molecular biology.

While most E. coli strains are harmless and even beneficial to their hosts, some serotypes can cause various forms of gastrointestinal and extraintestinal illnesses in humans and animals. These pathogenic strains possess virulence factors that enable them to colonize and damage host tissues, leading to diseases such as diarrhea, urinary tract infections, pneumonia, and sepsis.

E. coli is a versatile organism with remarkable genetic diversity, which allows it to adapt to various environmental niches. It can be found in water, soil, food, and various man-made environments, making it an essential indicator of fecal contamination and a common cause of foodborne illnesses. The study of E. coli has contributed significantly to our understanding of fundamental biological processes, including DNA replication, gene regulation, and protein synthesis.

Ubiquitin-protein ligases, also known as E3 ubiquitin ligases, are a group of enzymes that play a crucial role in the ubiquitination process. Ubiquitination is a post-translational modification where ubiquitin molecules are attached to specific target proteins, marking them for degradation by the proteasome or for other regulatory functions.

Ubiquitin-protein ligases catalyze the final step in this process by binding to both the ubiquitin protein and the target protein, facilitating the transfer of ubiquitin from an E2 ubiquitin-conjugating enzyme to the target protein. There are several different types of ubiquitin-protein ligases, each with their own specificity for particular target proteins and regulatory functions.

Ubiquitin-protein ligases have been implicated in various cellular processes such as protein degradation, DNA repair, signal transduction, and regulation of the cell cycle. Dysregulation of ubiquitination has been associated with several diseases, including cancer, neurodegenerative disorders, and inflammatory responses. Therefore, understanding the function and regulation of ubiquitin-protein ligases is an important area of research in biology and medicine.

An amino acid sequence is the specific order of amino acids in a protein or peptide molecule, formed by the linking of the amino group (-NH2) of one amino acid to the carboxyl group (-COOH) of another amino acid through a peptide bond. The sequence is determined by the genetic code and is unique to each type of protein or peptide. It plays a crucial role in determining the three-dimensional structure and function of proteins.

An anticodon is a sequence of three ribonucleotides (RNA bases) in a transfer RNA (tRNA) molecule that pair with a complementary codon in a messenger RNA (mRNA) molecule during protein synthesis. This interaction occurs within the ribosome during translation, where the genetic code in the mRNA is translated into an amino acid sequence in a polypeptide. Specifically, each tRNA carries a specific amino acid that corresponds to its anticodon sequence, allowing for the accurate and systematic addition of amino acids to the growing polypeptide chain.

In summary, an anticodon is a crucial component of the translation machinery, facilitating the precise decoding of genetic information and enabling the synthesis of proteins according to the instructions encoded in mRNA molecules.

DNA ligases are enzymes that catalyze the formation of a phosphodiester bond between two compatible ends of DNA molecules, effectively joining or "ligating" them together. There are several types of DNA ligases found in nature, each with specific functions and preferences for the type of DNA ends they can seal.

The most well-known DNA ligase is DNA ligase I, which plays a crucial role in replicating and repairing DNA in eukaryotic cells. It seals nicks or gaps in double-stranded DNA during replication and participates in the final step of DNA excision repair by rejoining the repaired strand to the original strand.

DNA ligase IV, another important enzyme, is primarily involved in the repair of double-strand breaks through a process called non-homologous end joining (NHEJ). This pathway is essential for maintaining genome stability and preventing chromosomal abnormalities.

Bacterial DNA ligases, such as T4 DNA ligase, are often used in molecular biology techniques due to their ability to join various types of DNA ends with high efficiency. These enzymes have been instrumental in the development of recombinant DNA technology and gene cloning methods.

Transfer RNA (tRNA) are small RNA molecules that play a crucial role in protein synthesis. They are responsible for translating the genetic code contained within messenger RNA (mRNA) into the specific sequence of amino acids during protein synthesis.

Amino acid-specific tRNAs are specialized tRNAs that recognize and bind to specific amino acids. Each tRNA has an anticodon region that can base-pair with a complementary codon on the mRNA, which determines the specific amino acid that will be added to the growing polypeptide chain during protein synthesis.

Therefore, a more detailed medical definition of "RNA, Transfer, Amino Acid-Specific" would be:

A type of transfer RNA (tRNA) molecule that is specific to a particular amino acid and plays a role in translating the genetic code contained within messenger RNA (mRNA) into the specific sequence of amino acids during protein synthesis. The anticodon region of an amino acid-specific tRNA base-pairs with a complementary codon on the mRNA, which determines the specific amino acid that will be added to the growing polypeptide chain during protein synthesis.

Transfer RNA (tRNA) is a type of RNA molecule that plays a crucial role in protein synthesis. It serves as the adaptor molecule that translates the genetic code present in messenger RNA (mRNA) into the corresponding amino acids, which are then linked together to form a polypeptide chain during protein synthesis.

Aminoacyl tRNA is a specific type of tRNA molecule that has been charged or activated with an amino acid. This process is called aminoacylation and is carried out by enzymes called aminoacyl-tRNA synthetases. Each synthetase specifically recognizes and attaches a particular amino acid to its corresponding tRNA, ensuring the fidelity of protein synthesis. Once an amino acid is attached to a tRNA, it forms an aminoacyl-tRNA complex, which can then participate in translation and contribute to the formation of a new protein.

A base sequence in the context of molecular biology refers to the specific order of nucleotides in a DNA or RNA molecule. In DNA, these nucleotides are adenine (A), guanine (G), cytosine (C), and thymine (T). In RNA, uracil (U) takes the place of thymine. The base sequence contains genetic information that is transcribed into RNA and ultimately translated into proteins. It is the exact order of these bases that determines the genetic code and thus the function of the DNA or RNA molecule.

Transfer RNA (tRNA) is a type of RNA molecule that plays a crucial role in protein synthesis in the cell. It carries and transfers specific amino acids to the growing polypeptide chain during translation, the process by which the genetic code in mRNA is translated into a protein sequence.

tRNAs have a characteristic cloverleaf-like secondary structure and a stem-loop tertiary structure, which allows them to bind both to specific amino acids and to complementary codon sequences on the messenger RNA (mRNA) through anticodons. This enables the precise matching of the correct amino acid to its corresponding codon in the mRNA during protein synthesis.

Ser, or serine, is one of the 20 standard amino acids that make up proteins. It is encoded by six different codons (UCU, UCC, UCA, UCG, AGU, and AGC) in the genetic code. The corresponding tRNA molecule that carries serine during protein synthesis is called tRNASer. There are multiple tRNASer isoacceptors, each with a different anticodon sequence but all carrying the same amino acid, serine.

Nucleic acid conformation refers to the three-dimensional structure that nucleic acids (DNA and RNA) adopt as a result of the bonding patterns between the atoms within the molecule. The primary structure of nucleic acids is determined by the sequence of nucleotides, while the conformation is influenced by factors such as the sugar-phosphate backbone, base stacking, and hydrogen bonding.

Two common conformations of DNA are the B-form and the A-form. The B-form is a right-handed helix with a diameter of about 20 Å and a pitch of 34 Å, while the A-form has a smaller diameter (about 18 Å) and a shorter pitch (about 25 Å). RNA typically adopts an A-form conformation.

The conformation of nucleic acids can have significant implications for their function, as it can affect their ability to interact with other molecules such as proteins or drugs. Understanding the conformational properties of nucleic acids is therefore an important area of research in molecular biology and medicine.

Aspartate kinase is a type of enzyme that plays a crucial role in the biosynthesis of several amino acids, including aspartate, methionine, and threonine. This enzyme catalyzes the phosphorylation of aspartic acid to form phosphoaspartate, which is the first step in the synthesis of these essential amino acids.

Aspartate kinase exists in different forms or isozymes in various organisms, and it can be regulated by feedback inhibition. This means that the enzyme's activity can be suppressed when the concentration of one or more of the amino acids it helps to synthesize becomes too high, preventing further production and maintaining a balanced level of these essential nutrients in the body.

In humans, aspartate kinase is involved in several metabolic pathways and is an essential enzyme for normal growth and development. Defects or mutations in the genes encoding aspartate kinase can lead to various genetic disorders and metabolic imbalances.

Ubiquitination is a post-translational modification process in which a ubiquitin protein is covalently attached to a target protein. This process plays a crucial role in regulating various cellular functions, including protein degradation, DNA repair, and signal transduction. The addition of ubiquitin can lead to different outcomes depending on the number and location of ubiquitin molecules attached to the target protein. Monoubiquitination (the attachment of a single ubiquitin molecule) or multiubiquitination (the attachment of multiple ubiquitin molecules) can mark proteins for degradation by the 26S proteasome, while specific types of ubiquitination (e.g., K63-linked polyubiquitination) can serve as a signal for nonproteolytic functions such as endocytosis, autophagy, or DNA repair. Ubiquitination is a highly regulated process that involves the coordinated action of three enzymes: E1 ubiquitin-activating enzyme, E2 ubiquitin-conjugating enzyme, and E3 ubiquitin ligase. Dysregulation of ubiquitination has been implicated in various diseases, including cancer, neurodegenerative disorders, and inflammatory conditions.

Transfer RNA (tRNA) is a type of RNA molecule that helps translate genetic information from messenger RNA (mRNA) into proteins. Each tRNA carries a specific amino acid to the growing polypeptide chain during protein synthesis, based on the anticodon sequence in its variable loop region that recognizes and binds to a complementary codon sequence in the mRNA.

Phenylalanine (Phe) is one of the twenty standard amino acids found in proteins. It has a hydrophobic side chain, which means it tends to repel water and interact with other non-polar molecules. In tRNA, phenylalanine is attached to a specific tRNA molecule known as tRNAPhe. This tRNA recognizes the mRNA codons UUC and UUU, which specify phenylalanine during protein synthesis.

Ubiquitin-Protein Ligase Complexes, also known as E3 ubiquitin ligases, are a group of enzymes that play a crucial role in the ubiquitination process. Ubiquitination is a post-translational modification where ubiquitin molecules are attached to specific target proteins, marking them for degradation by the proteasome or altering their function, localization, or interaction with other proteins.

The ubiquitination process involves three main steps:

1. Ubiquitin activation: Ubiquitin is activated by an E1 ubiquitin-activating enzyme in an ATP-dependent reaction.
2. Ubiquitin conjugation: The activated ubiquitin is then transferred to an E2 ubiquitin-conjugating enzyme.
3. Ubiquitin ligation: Finally, the E2 ubiquitin-conjugating enzyme interacts with a specific E3 ubiquitin ligase complex, which facilitates the transfer and ligation of ubiquitin to the target protein.

Ubiquitin-Protein Ligase Complexes are responsible for recognizing and binding to specific substrate proteins, ensuring that ubiquitination occurs on the correct targets. They can be divided into three main categories based on their structural features and mechanisms of action:

1. Really Interesting New Gene (RING) finger E3 ligases: These E3 ligases contain a RING finger domain, which directly interacts with both the E2 ubiquitin-conjugating enzyme and the substrate protein. They facilitate the transfer of ubiquitin from the E2 to the target protein by bringing them into close proximity.
2. Homologous to E6-AP C terminus (HECT) E3 ligases: These E3 ligases contain a HECT domain, which interacts with the E2 ubiquitin-conjugating enzyme and forms a thioester bond with ubiquitin before transferring it to the substrate protein.
3. RING-between-RING (RBR) E3 ligases: These E3 ligases contain both RING finger and HECT-like domains, which allow them to function similarly to both RING finger and HECT E3 ligases. They first form a thioester bond with ubiquitin using their RING1 domain before transferring it to the substrate protein via their RING2 domain.

Dysregulation of Ubiquitin-Protein Ligase Complexes has been implicated in various diseases, including cancer and neurodegenerative disorders. Understanding their mechanisms and functions can provide valuable insights into disease pathogenesis and potential therapeutic strategies.

Transfer RNA (tRNA) for tryptophan (Trp) is a specific type of tRNA molecule that plays a crucial role in protein synthesis. In the process of translation, genetic information from messenger RNA (mRNA) is translated into a corresponding sequence of amino acids to form a protein.

Tryptophan is one of the twenty standard amino acids found in proteins. Each tRNA molecule carries a specific amino acid that corresponds to a particular codon (a sequence of three nucleotides) on the mRNA. The tRNA with tryptophan attached to it recognizes and binds to the mRNA codon UGG, which is the only codon that specifies tryptophan in the genetic code.

The tRNA molecule has a characteristic cloverleaf-like structure, composed of a stem region made up of base pairs and loop regions containing unpaired nucleotides. The anticodon loop contains the complementary sequence to the mRNA codon, allowing for specific recognition and binding. The other end of the tRNA molecule carries the amino acid, in this case tryptophan, which is attached via an ester linkage to a specific nucleotide called the 3'-end of the tRNA.

In summary, tRNA (Trp) is a key player in protein synthesis, responsible for delivering tryptophan to the ribosome during translation, where it can be incorporated into the growing polypeptide chain according to the genetic information encoded in mRNA.

I believe there may be a slight error in the term you're asking about. "Asp" doesn't specifically relate to RNA (Ribonucleic Acid) or its types. However, I can provide a definition for "Transfer RNA" (tRNA).

Transfer RNA (tRNA) is a type of RNA that plays a crucial role in protein synthesis. It carries and transfers specific amino acids to the growing polypeptide chain during translation, according to the genetic code provided by messenger RNA (mRNA). Each tRNA molecule has an anticodon region which can base-pair with a complementary codon in the mRNA, and a corresponding amino acid attached to its other end. This enables the correct matching of amino acids to form proteins according to the genetic information encoded in mRNA.

I'm happy to help! However, it seems like the term you're looking for is "Transfer RNA arginine," not "Arg." Transfer RNA (tRNA) is a type of RNA molecule that plays a crucial role in protein synthesis. Specifically, tRNAs are responsible for delivering amino acids to the ribosome, where they are joined together to form proteins.

Each tRNA molecule contains a specific anticodon sequence that can base-pair with a complementary codon sequence on messenger RNA (mRNA). When a tRNA molecule encounters an mRNA codon that matches its anticodon, it binds to the mRNA and delivers the amino acid associated with that tRNA.

In the case of tRNA arginine, this type of tRNA is responsible for delivering the amino acid arginine to the ribosome during protein synthesis. Arginine is a positively charged amino acid that plays important roles in various cellular processes, including protein structure and function, signal transduction, and gene regulation.

Therefore, Transfer RNA arginine refers to the specific tRNA molecule that delivers the amino acid arginine during protein synthesis.

Ligases are a group of enzymes that catalyze the formation of a covalent bond between two molecules, usually involving the joining of two nucleotides in a DNA or RNA strand. They play a crucial role in various biological processes such as DNA replication, repair, and recombination. In DNA ligases, the enzyme seals nicks or breaks in the phosphodiester backbone of the DNA molecule by catalyzing the formation of an ester bond between the 3'-hydroxyl group and the 5'-phosphate group of adjacent nucleotides. This process is essential for maintaining genomic integrity and stability.

A mutation is a permanent change in the DNA sequence of an organism's genome. Mutations can occur spontaneously or be caused by environmental factors such as exposure to radiation, chemicals, or viruses. They may have various effects on the organism, ranging from benign to harmful, depending on where they occur and whether they alter the function of essential proteins. In some cases, mutations can increase an individual's susceptibility to certain diseases or disorders, while in others, they may confer a survival advantage. Mutations are the driving force behind evolution, as they introduce new genetic variability into populations, which can then be acted upon by natural selection.

Cullin proteins are a family of structurally related proteins that play a crucial role in the function of E3 ubiquitin ligase complexes. These complexes are responsible for targeting specific cellular proteins for degradation by the proteasome, which is a key process in maintaining protein homeostasis within cells.

Cullin proteins act as scaffolds that bring together different components of the E3 ubiquitin ligase complex, including RING finger proteins and substrate receptors. There are several different cullin proteins identified in humans (CUL1, CUL2, CUL3, CUL4A, CUL4B, CUL5, and CUL7), each of which can form distinct E3 ubiquitin ligase complexes with unique substrate specificities.

The regulation of cullin proteins is critical for normal cellular function, and dysregulation of these proteins has been implicated in various diseases, including cancer. For example, mutations in CUL1 have been found in certain types of breast and ovarian cancers, while alterations in CUL3 have been linked to neurodegenerative disorders such as Parkinson's disease.

Overall, cullin proteins are essential components of the ubiquitin-proteasome system, which plays a critical role in regulating protein turnover and maintaining cellular homeostasis.

Transfer RNA (tRNA) is a type of RNA molecule that plays a crucial role in protein synthesis, the process by which cells create proteins. During protein synthesis, tRNAs serve as adaptors, translating the genetic code present in messenger RNA (mRNA) into the corresponding amino acids required to build a protein.

Each tRNA molecule has an anticodon region that can base-pair with specific codons (three-nucleotide sequences) on the mRNA. At the other end of the tRNA is the acceptor stem, which contains a binding site for the corresponding amino acid. When an amino acid attaches to the tRNA, it forms an ester bond between the carboxyl group of the amino acid and the 3'-hydroxyl group of the ribose in the tRNA. This aminoacylated tRNA then participates in the translation process, delivering the amino acid to the growing polypeptide chain at the ribosome.

In summary, transfer RNA (tRNA) is a type of RNA molecule that facilitates protein synthesis by transporting and delivering specific amino acids to the ribosome for incorporation into a polypeptide chain, based on the codon-anticodon pairing between tRNAs and messenger RNA (mRNA).

Transfer RNA (tRNA) is a type of RNA molecule that plays a crucial role in protein synthesis. During this process, tRNAs serve as adaptors between the mRNA (messenger RNA) molecules and the amino acids used to construct proteins. Each tRNA contains a specific anticodon sequence that can base-pair with a complementary codon on the mRNA. At the other end of the tRNA, there is a site where an amino acid can attach. This attachment is facilitated by enzymes called aminoacyl tRNA synthetases, which recognize specific tRNAs and catalyze the formation of the ester bond between the tRNA and its cognate amino acid.

Gly (glycine) is one of the 20 standard amino acids found in proteins. It has a simple structure, consisting of an amino group (-NH2), a carboxylic acid group (-COOH), a hydrogen atom (-H), and a side chain made up of a single hydrogen atom (-CH2-). Glycine is the smallest and most flexible of all amino acids due to its lack of a bulky side chain, which allows it to fit into tight spaces within protein structures.

Therefore, 'RNA, Transfer, Gly' can be understood as a transfer RNA (tRNA) molecule specifically responsible for delivering the amino acid glycine (-Gly) during protein synthesis. This tRNA will have an anticodon sequence that base-pairs with the mRNA codons specifying glycine: GGU, GGC, GGA, or GGG.

Transfer RNA (tRNA) that carries the amino acid isoleucine is referred to as 'tRNA-Ile' in medical and molecular biology terminology.

tRNAs are specialized RNA molecules that play a crucial role in protein synthesis, by transporting specific amino acids from the cytoplasm to the ribosomes, where proteins are assembled. Each tRNA has an anticodon region that recognizes and binds to a complementary codon sequence on messenger RNA (mRNA). When a tRNA with the correct anticodon pairs with an mRNA codon during translation, the attached amino acid is added to the growing polypeptide chain.

Ile, or isoleucine, is a genetically encoded, hydrophobic amino acid that is one of the 20 standard amino acids found in proteins. Isoleucine is transported by its specific tRNA-Ile molecule during protein synthesis.

Ubiquitin is a small protein that is present in all eukaryotic cells and plays a crucial role in the regulation of various cellular processes, such as protein degradation, DNA repair, and stress response. It is involved in marking proteins for destruction by attaching to them, a process known as ubiquitination. This modification can target proteins for degradation by the proteasome, a large protein complex that breaks down unneeded or damaged proteins in the cell. Ubiquitin also has other functions, such as regulating the localization and activity of certain proteins. The ability of ubiquitin to modify many different proteins and play a role in multiple cellular processes makes it an essential player in maintaining cellular homeostasis.

In the context of medicine and pharmacology, "kinetics" refers to the study of how a drug moves throughout the body, including its absorption, distribution, metabolism, and excretion (often abbreviated as ADME). This field is called "pharmacokinetics."

1. Absorption: This is the process of a drug moving from its site of administration into the bloodstream. Factors such as the route of administration (e.g., oral, intravenous, etc.), formulation, and individual physiological differences can affect absorption.

2. Distribution: Once a drug is in the bloodstream, it gets distributed throughout the body to various tissues and organs. This process is influenced by factors like blood flow, protein binding, and lipid solubility of the drug.

3. Metabolism: Drugs are often chemically modified in the body, typically in the liver, through processes known as metabolism. These changes can lead to the formation of active or inactive metabolites, which may then be further distributed, excreted, or undergo additional metabolic transformations.

4. Excretion: This is the process by which drugs and their metabolites are eliminated from the body, primarily through the kidneys (urine) and the liver (bile).

Understanding the kinetics of a drug is crucial for determining its optimal dosing regimen, potential interactions with other medications or foods, and any necessary adjustments for special populations like pediatric or geriatric patients, or those with impaired renal or hepatic function.

'RNA, Transfer, Ala' refers to a specific type of transfer RNA (tRNA) molecule that is involved in protein synthesis. In molecular biology, the term 'RNA' stands for ribonucleic acid, which is a nucleic acid present in the cells of all living organisms. Transfer RNAs are a type of RNA that help translate genetic information from messenger RNA (mRNA) into proteins during the process of protein synthesis or translation.

'Transfer, Ala' more specifically refers to a transfer RNA molecule that carries the amino acid alanine (Ala) to the ribosome during protein synthesis. Each tRNA has a specific anticodon sequence that can base-pair with a complementary codon sequence in the mRNA, and it also carries a specific amino acid that corresponds to that codon. In this case, the anticodon on the 'Transfer, Ala' tRNA molecule is capable of base-pairing with any one of the three codons (GCU, GCC, GCA, or GCG) that specify alanine in the genetic code.

Therefore, 'RNA, Transfer, Ala' can be defined as a type of transfer RNA molecule that carries and delivers the amino acid alanine to the growing polypeptide chain during protein synthesis.

Glutamate-cysteine ligase (GCL) is an essential enzyme in the biosynthesis of glutathione, a major antioxidant in cells. It catalyzes the reaction between glutamate and cysteine to form γ-glutamylcysteine, which is then combined with glycine by glutathione synthetase to produce glutathione.

GCL has two subunits: a catalytic subunit (GCLC) and a modulatory subunit (GCLM). The former contains the active site for the formation of the peptide bond between glutamate and cysteine, while the latter regulates the activity of GCLC by affecting its sensitivity to feedback inhibition by glutathione.

The proper functioning of GCL is critical for maintaining cellular redox homeostasis and protecting against oxidative stress, making it a potential target for therapeutic intervention in various diseases associated with oxidative damage, such as neurodegenerative disorders, cancer, and aging-related conditions.

Transfer RNA (tRNA) that is specific for the amino acid glutamic acid (Glu or E) is referred to as "tRNA-Glu" or "tRNAGlu." This tRNA carries the amino acid glutamic acid to the ribosome during protein synthesis, where it gets incorporated into a growing polypeptide chain according to the genetic code.

The transfer RNA molecules are small adaptor molecules that facilitate translation of the genetic code present in messenger RNA (mRNA) into the corresponding amino acid sequence of proteins. Each tRNA has an anticodon region, which recognizes and binds to a specific codon on the mRNA through base-pairing interactions. The other end of the tRNA contains a binding site for the corresponding amino acid, ensuring that the correct amino acid is added during protein synthesis.

In summary, "tRNA-Glu" or "tRNAGlu" refers to the specific transfer RNA molecule responsible for transporting and incorporating glutamic acid into proteins during translation.

Transfer RNA (tRNA) is a type of RNA molecule that plays a crucial role in protein synthesis in the cell. It carries amino acids to the ribosome, where they are joined together in a specific sequence to form a polypeptide chain, which eventually becomes a protein.

Each tRNA molecule has a unique structure and is responsible for carrying a specific amino acid to the ribosome during protein synthesis. The amino acids are attached to the tRNA at a site called the acceptor stem, which contains a three-base sequence known as the anticodon.

Val (or V) is one of the twenty standard amino acids found in proteins. It stands for Valine, and its codons are GUA, GUC, GUG, and GUU. Therefore, tRNA Val refers to a specific type of transfer RNA molecule that carries valine to the ribosome during protein synthesis.

Alanine transaminase (ALT) is a type of enzyme found primarily in the cells of the liver and, to a lesser extent, in the cells of other tissues such as the heart, muscles, and kidneys. Its primary function is to catalyze the reversible transfer of an amino group from alanine to another alpha-keto acid, usually pyruvate, to form pyruvate and another amino acid, usually glutamate. This process is known as the transamination reaction.

When liver cells are damaged or destroyed due to various reasons such as hepatitis, alcohol abuse, nonalcoholic fatty liver disease, or drug-induced liver injury, ALT is released into the bloodstream. Therefore, measuring the level of ALT in the blood is a useful diagnostic tool for evaluating liver function and detecting liver damage. Normal ALT levels vary depending on the laboratory, but typically range from 7 to 56 units per liter (U/L) for men and 6 to 45 U/L for women. Elevated ALT levels may indicate liver injury or disease, although other factors such as muscle damage or heart disease can also cause elevations in ALT.

Aspartate ammonia-lyase is an enzyme that plays a role in the metabolism of certain amino acids. Its systematic name is L-aspartate ammonia-lyase (ADI), and it is also known as aspartase. This enzyme is responsible for catalyzing the conversion of L-aspartic acid to fumaric acid and ammonia.

L-aspartic acid + H2O → fumaric acid + NH3

Aspartate ammonia-lyase is found in various organisms, including bacteria, fungi, and plants. In bacteria, this enzyme is involved in the biosynthesis of several essential amino acids. In plants, aspartate ammonia-lyase plays a role in the synthesis of certain aromatic compounds. The human body does not produce this enzyme, so it is not relevant to medical definitions in the context of human health and disease.

In the context of medical and biological sciences, a "binding site" refers to a specific location on a protein, molecule, or cell where another molecule can attach or bind. This binding interaction can lead to various functional changes in the original protein or molecule. The other molecule that binds to the binding site is often referred to as a ligand, which can be a small molecule, ion, or even another protein.

The binding between a ligand and its target binding site can be specific and selective, meaning that only certain ligands can bind to particular binding sites with high affinity. This specificity plays a crucial role in various biological processes, such as signal transduction, enzyme catalysis, or drug action.

In the case of drug development, understanding the location and properties of binding sites on target proteins is essential for designing drugs that can selectively bind to these sites and modulate protein function. This knowledge can help create more effective and safer therapeutic options for various diseases.

Transfer RNA (tRNA) that carries glutamine (Gln) is a type of RNA molecule involved in protein synthesis. Glutamine is one of the twenty standard amino acids used by cells to construct proteins. During protein synthesis, tRNAs serve as adaptors between the mRNA code and the corresponding amino acids. Specifically, the tRNA with the anticodon complementary to the mRNA codon for glutamine (CAA or CAG) binds to glutamine and delivers it to the growing polypeptide chain during translation. This particular tRNA is referred to as 'tRNA Gln' or 'tRNA for Gln'.

Substrate specificity in the context of medical biochemistry and enzymology refers to the ability of an enzyme to selectively bind and catalyze a chemical reaction with a particular substrate (or a group of similar substrates) while discriminating against other molecules that are not substrates. This specificity arises from the three-dimensional structure of the enzyme, which has evolved to match the shape, charge distribution, and functional groups of its physiological substrate(s).

Substrate specificity is a fundamental property of enzymes that enables them to carry out highly selective chemical transformations in the complex cellular environment. The active site of an enzyme, where the catalysis takes place, has a unique conformation that complements the shape and charge distribution of its substrate(s). This ensures efficient recognition, binding, and conversion of the substrate into the desired product while minimizing unwanted side reactions with other molecules.

Substrate specificity can be categorized as:

1. Absolute specificity: An enzyme that can only act on a single substrate or a very narrow group of structurally related substrates, showing no activity towards any other molecule.
2. Group specificity: An enzyme that prefers to act on a particular functional group or class of compounds but can still accommodate minor structural variations within the substrate.
3. Broad or promiscuous specificity: An enzyme that can act on a wide range of structurally diverse substrates, albeit with varying catalytic efficiencies.

Understanding substrate specificity is crucial for elucidating enzymatic mechanisms, designing drugs that target specific enzymes or pathways, and developing biotechnological applications that rely on the controlled manipulation of enzyme activities.

Transfer RNA (tRNA) is a type of RNA molecule that plays a crucial role in protein synthesis, the process by which cells create proteins. In protein synthesis, tRNAs serve as adaptors, translating the genetic code present in messenger RNA (mRNA) into the corresponding amino acids required to build a protein.

tRNAs have a distinct cloverleaf-like secondary structure and a compact L-shaped tertiary structure. Each tRNA molecule contains a specific anticodon triplet nucleotide sequence that can base-pair with a complementary codon in the mRNA during translation. At the other end of the tRNA, there is an amino acid attachment site where the corresponding amino acid is covalently attached through the action of aminoacyl-tRNA synthetase enzymes.

Pro (also known as proline) is a specific amino acid that can be carried by certain tRNAs during protein synthesis. Therefore, in a medical definition context, 'RNA, Transfer, Pro' would refer to the transfer RNA molecule(s) specifically responsible for carrying and delivering proline during protein synthesis. This tRNA is typically denoted as tRNA^Pro^ or tRNA-Pro, with the superscript indicating the specific amino acid it carries.

Transfer RNA (tRNA) is a type of RNA molecule that plays a crucial role in protein synthesis. It carries amino acids to the ribosome, where they are incorporated into growing polypeptide chains during translation, the process by which the genetic code in mRNA is translated into a protein sequence.

tRNAs have a characteristic cloverleaf-like secondary structure and a stem-loop tertiary structure, which allows them to recognize specific codons on the mRNA through base-pairing between their anticodon loops and the complementary codons. Each tRNA is specific for one amino acid, and there are multiple tRNAs for each amino acid that differ in their anticodon sequences, allowing them to recognize different codons that specify the same amino acid.

"His" refers to the amino acid Histidine, which is encoded by the codons CAU and CAC on mRNA. Therefore, tRNA-His is a type of tRNA molecule that carries the amino acid Histidine to the ribosome during protein synthesis.

Protein binding, in the context of medical and biological sciences, refers to the interaction between a protein and another molecule (known as the ligand) that results in a stable complex. This process is often reversible and can be influenced by various factors such as pH, temperature, and concentration of the involved molecules.

In clinical chemistry, protein binding is particularly important when it comes to drugs, as many of them bind to proteins (especially albumin) in the bloodstream. The degree of protein binding can affect a drug's distribution, metabolism, and excretion, which in turn influence its therapeutic effectiveness and potential side effects.

Protein-bound drugs may be less available for interaction with their target tissues, as only the unbound or "free" fraction of the drug is active. Therefore, understanding protein binding can help optimize dosing regimens and minimize adverse reactions.

Amino acid receptors are a type of cell surface receptor that bind to specific amino acids or peptides and trigger intracellular signaling pathways. These receptors play important roles in various physiological processes, including neurotransmission, hormone signaling, and regulation of metabolism.

There are several types of amino acid receptors, including:

1. G protein-coupled receptors (GPCRs): These receptors are activated by amino acids such as γ-aminobutyric acid (GABA), glycine, and glutamate, and play important roles in neurotransmission and neuromodulation.
2. Ionotropic receptors: These receptors are ligand-gated ion channels that are activated by amino acids such as glutamate and glycine. They play critical roles in synaptic transmission and neural excitability.
3. Enzyme-linked receptors: These receptors activate intracellular signaling pathways through the activation of enzymes, such as receptor tyrosine kinases (RTKs). Some amino acid receptors, such as the insulin-like growth factor 1 receptor (IGF-1R), are RTKs that play important roles in cell growth, differentiation, and metabolism.
4. Intracellular receptors: These receptors are located within the cell and bind to amino acids or peptides that have been transported into the cell. For example, the peroxisome proliferator-activated receptors (PPARs) are intracellular receptors that bind to fatty acids and play important roles in lipid metabolism and inflammation.

Overall, amino acid receptors are critical components of cell signaling pathways and play important roles in various physiological processes. Dysregulation of these receptors has been implicated in a variety of diseases, including neurological disorders, cancer, and metabolic disorders.

Bacterial RNA refers to the genetic material present in bacteria that is composed of ribonucleic acid (RNA). Unlike higher organisms, bacteria contain a single circular chromosome made up of DNA, along with smaller circular pieces of DNA called plasmids. These bacterial genetic materials contain the information necessary for the growth and reproduction of the organism.

Bacterial RNA can be divided into three main categories: messenger RNA (mRNA), ribosomal RNA (rRNA), and transfer RNA (tRNA). mRNA carries genetic information copied from DNA, which is then translated into proteins by the rRNA and tRNA molecules. rRNA is a structural component of the ribosome, where protein synthesis occurs, while tRNA acts as an adapter that brings amino acids to the ribosome during protein synthesis.

Bacterial RNA plays a crucial role in various cellular processes, including gene expression, protein synthesis, and regulation of metabolic pathways. Understanding the structure and function of bacterial RNA is essential for developing new antibiotics and other therapeutic strategies to combat bacterial infections.

Molecular models are three-dimensional representations of molecular structures that are used in the field of molecular biology and chemistry to visualize and understand the spatial arrangement of atoms and bonds within a molecule. These models can be physical or computer-generated and allow researchers to study the shape, size, and behavior of molecules, which is crucial for understanding their function and interactions with other molecules.

Physical molecular models are often made up of balls (representing atoms) connected by rods or sticks (representing bonds). These models can be constructed manually using materials such as plastic or wooden balls and rods, or they can be created using 3D printing technology.

Computer-generated molecular models, on the other hand, are created using specialized software that allows researchers to visualize and manipulate molecular structures in three dimensions. These models can be used to simulate molecular interactions, predict molecular behavior, and design new drugs or chemicals with specific properties. Overall, molecular models play a critical role in advancing our understanding of molecular structures and their functions.

Glutamates are the salt or ester forms of glutamic acid, which is a naturally occurring amino acid and the most abundant excitatory neurotransmitter in the central nervous system. Glutamate plays a crucial role in various brain functions, such as learning, memory, and cognition. However, excessive levels of glutamate can lead to neuronal damage or death, contributing to several neurological disorders, including stroke, epilepsy, and neurodegenerative diseases like Alzheimer's and Parkinson's.

Glutamates are also commonly found in food as a natural flavor enhancer, often listed under the name monosodium glutamate (MSG). While MSG has been extensively studied, its safety remains a topic of debate, with some individuals reporting adverse reactions after consuming foods containing this additive.

Ligase Chain Reaction (LCR) is a highly specific and sensitive method used in molecular biology for the detection of point mutations or small deletions or insertions in DNA. It is an enzymatic reaction-based technique that relies on the repeated ligation of adjacent oligonucleotide probes to form a continuous strand, followed by thermal denaturation and reannealing of the strands.

The LCR process involves the use of a thermostable ligase enzyme, which catalyzes the formation of a phosphodiester bond between two adjacent oligonucleotide probes that are hybridized to complementary sequences in the target DNA. The oligonucleotides are designed to have a gap at the site of the mutation or deletion/insertion, such that ligation can only occur if the probe sequences match perfectly with the target DNA.

After each round of ligation and denaturation, the reaction mixture is subjected to PCR amplification using primers flanking the region of interest. The amplified products are then analyzed for the presence or absence of ligated probes, indicating the presence or absence of the mutation or deletion/insertion in the target DNA.

LCR has been widely used in diagnostic and research applications, including the detection of genetic diseases, infectious agents, and cancer-associated mutations. However, it has largely been replaced by other more sensitive and high-throughput methods such as real-time PCR and next-generation sequencing.

SKP (S-phase kinase associated protein) Cullin F-box protein ligases, also known as SCF complexes, are a type of E3 ubiquitin ligase that play a crucial role in the ubiquitination and subsequent degradation of proteins. These complexes are composed of several subunits: SKP1, Cul1 (Cullin 1), Rbx1 (Ring-box 1), and an F-box protein. The F-box protein is a variable component that determines the substrate specificity of the SCF complex.

The ubiquitination process mediated by SCF complexes involves the sequential transfer of ubiquitin molecules to a target protein, leading to its degradation by the 26S proteasome. This pathway is essential for various cellular processes, including cell cycle regulation, signal transduction, and DNA damage response.

Dysregulation of SCF complexes has been implicated in several diseases, such as cancer and neurodegenerative disorders, making them potential targets for therapeutic intervention.

Tertiary protein structure refers to the three-dimensional arrangement of all the elements (polypeptide chains) of a single protein molecule. It is the highest level of structural organization and results from interactions between various side chains (R groups) of the amino acids that make up the protein. These interactions, which include hydrogen bonds, ionic bonds, van der Waals forces, and disulfide bridges, give the protein its unique shape and stability, which in turn determines its function. The tertiary structure of a protein can be stabilized by various factors such as temperature, pH, and the presence of certain ions. Any changes in these factors can lead to denaturation, where the protein loses its tertiary structure and thus its function.

A codon is a sequence of three adjacent nucleotides in DNA or RNA that specifies the insertion of a particular amino acid during protein synthesis, or signals the beginning or end of translation. In DNA, these triplets are read during transcription to produce a complementary mRNA molecule, which is then translated into a polypeptide chain during translation. There are 64 possible codons in the standard genetic code, with 61 encoding for specific amino acids and three serving as stop codons that signal the termination of protein synthesis.

Aspartate aminotransferase (AST), mitochondrial isoform, is an enzyme found primarily in the mitochondria of cells. It is involved in the transfer of an amino group from aspartic acid to alpha-ketoglutarate, resulting in the formation of oxaloacetate and glutamate. This enzyme plays a crucial role in the cellular energy production process, particularly within the mitochondria.

Elevated levels of AST, mitochondrial isoform, can be found in various medical conditions, including liver disease, muscle damage, and heart injury. However, it's important to note that most clinical laboratories measure a combined level of both cytosolic and mitochondrial AST isoforms when testing for this enzyme. Therefore, the specific contribution of the mitochondrial isoform may not be easily discernible in routine medical tests.

Amino acids are organic compounds that serve as the building blocks of proteins. They consist of a central carbon atom, also known as the alpha carbon, which is bonded to an amino group (-NH2), a carboxyl group (-COOH), a hydrogen atom (H), and a variable side chain (R group). The R group can be composed of various combinations of atoms such as hydrogen, oxygen, sulfur, nitrogen, and carbon, which determine the unique properties of each amino acid.

There are 20 standard amino acids that are encoded by the genetic code and incorporated into proteins during translation. These include:

1. Alanine (Ala)
2. Arginine (Arg)
3. Asparagine (Asn)
4. Aspartic acid (Asp)
5. Cysteine (Cys)
6. Glutamine (Gln)
7. Glutamic acid (Glu)
8. Glycine (Gly)
9. Histidine (His)
10. Isoleucine (Ile)
11. Leucine (Leu)
12. Lysine (Lys)
13. Methionine (Met)
14. Phenylalanine (Phe)
15. Proline (Pro)
16. Serine (Ser)
17. Threonine (Thr)
18. Tryptophan (Trp)
19. Tyrosine (Tyr)
20. Valine (Val)

Additionally, there are several non-standard or modified amino acids that can be incorporated into proteins through post-translational modifications, such as hydroxylation, methylation, and phosphorylation. These modifications expand the functional diversity of proteins and play crucial roles in various cellular processes.

Amino acids are essential for numerous biological functions, including protein synthesis, enzyme catalysis, neurotransmitter production, energy metabolism, and immune response regulation. Some amino acids can be synthesized by the human body (non-essential), while others must be obtained through dietary sources (essential).

F-box proteins are a family of proteins that are characterized by the presence of an F-box domain, which is a motif of about 40-50 amino acids. This domain is responsible for binding to Skp1, a component of the SCF (Skp1-Cul1-F-box protein) E3 ubiquitin ligase complex. The F-box proteins serve as the substrate recognition subunit of this complex and are involved in targeting specific proteins for ubiquitination and subsequent degradation by the 26S proteasome.

There are multiple types of F-box proteins, including FBXW (also known as β-TrCP), FBXL, and FBLX, each with different substrate specificities. These proteins play important roles in various cellular processes such as cell cycle regulation, signal transduction, and DNA damage response by controlling the stability of key regulatory proteins.

Abnormal regulation of F-box proteins has been implicated in several human diseases, including cancer, developmental disorders, and neurodegenerative diseases.

Transfer RNA (tRNA) is a type of RNA molecule that plays a crucial role in protein synthesis in the cell. It carries amino acids to the ribosome, where they are joined together in a specific sequence to form a polypeptide chain, which ultimately becomes a protein.

Each tRNA molecule has a unique structure and is responsible for carrying a specific amino acid. The genetic information that specifies which amino acid a particular tRNA carries is encoded in the form of a three-nucleotide sequence called an anticodon, which is located on one end of the tRNA molecule.

Threonine (Thr) is one of the twenty standard amino acids found in proteins. It is encoded by the codons ACU, ACA, ACC, and ACG in the genetic code. Therefore, a tRNA molecule with an anticodon complementary to any of these codons will carry threonine during protein synthesis.

So, to provide a medical definition of 'RNA, Transfer, Thr', it would be: A type of transfer RNA (tRNA) that carries the amino acid threonine (Thr) to the ribosome during protein synthesis and has an anticodon sequence complementary to one or more of the codons ACU, ACA, ACC, or ACG.

Phosphonoacetic acid (PAA) is not a naturally occurring substance, but rather a synthetic compound that is used in medical and scientific research. It is a colorless, crystalline solid that is soluble in water.

In a medical context, PAA is an inhibitor of certain enzymes that are involved in the replication of viruses, including HIV. It works by binding to the active site of these enzymes and preventing them from carrying out their normal functions. As a result, PAA has been studied as a potential antiviral agent, although it is not currently used as a medication.

It's important to note that while PAA has shown promise in laboratory studies, its safety and efficacy have not been established in clinical trials, and it is not approved for use as a drug by regulatory agencies such as the U.S. Food and Drug Administration (FDA).

Ubiquitin-conjugating enzymes (UBCs or E2 enzymes) are a family of enzymes that play a crucial role in the ubiquitination process, which is a post-translational modification of proteins. This process involves the covalent attachment of the protein ubiquitin to specific lysine residues on target proteins, ultimately leading to their degradation by the 26S proteasome.

Ubiquitination is a multi-step process that requires the coordinated action of three types of enzymes: E1 (ubiquitin-activating), E2 (ubiquitin-conjugating), and E3 (ubiquitin ligases). Ubiquitin-conjugating enzymes are responsible for transferring ubiquitin from the E1 enzyme to the target protein, which is facilitated by an E3 ubiquitin ligase. The human genome encodes around 40 different UBCs, each with unique substrate specificities and functions in various cellular processes, such as protein degradation, DNA repair, and signal transduction.

Ubiquitination is a highly regulated process that can be reversed by the action of deubiquitinating enzymes (DUBs), which remove ubiquitin molecules from target proteins. Dysregulation of the ubiquitination pathway has been implicated in various diseases, including cancer, neurodegenerative disorders, and inflammatory conditions.

Site-directed mutagenesis is a molecular biology technique used to introduce specific and targeted changes to a specific DNA sequence. This process involves creating a new variant of a gene or a specific region of interest within a DNA molecule by introducing a planned, deliberate change, or mutation, at a predetermined site within the DNA sequence.

The methodology typically involves the use of molecular tools such as PCR (polymerase chain reaction), restriction enzymes, and/or ligases to introduce the desired mutation(s) into a plasmid or other vector containing the target DNA sequence. The resulting modified DNA molecule can then be used to transform host cells, allowing for the production of large quantities of the mutated gene or protein for further study.

Site-directed mutagenesis is a valuable tool in basic research, drug discovery, and biotechnology applications where specific changes to a DNA sequence are required to understand gene function, investigate protein structure/function relationships, or engineer novel biological properties into existing genes or proteins.

Aminoacylation is a biochemical process in which an amino acid is linked to a transfer RNA (tRNA) molecule through the formation of an ester bond. This reaction is catalyzed by an enzyme called an aminoacyl-tRNA synthetase, which specifically recognizes and activates a particular amino acid and then attaches it to the appropriate tRNA molecule.

The resulting aminoacyl-tRNA complexes are essential for protein synthesis in all living organisms. During translation, the genetic information encoded in messenger RNA (mRNA) is used to direct the sequential addition of amino acids to a growing polypeptide chain. Each aminoacyl-tRNA molecule carries a specific amino acid that corresponds to a particular codon in the mRNA, ensuring that the correct amino acids are added to the protein in the proper order.

Therefore, the process of aminoacylation plays a crucial role in maintaining the fidelity and accuracy of protein synthesis, as well as contributing to the regulation of gene expression and the maintenance of cellular homeostasis.

Serine-tRNA ligase is an enzyme that plays a crucial role in protein synthesis, specifically in the attachment of the amino acid serine to its corresponding transfer RNA (tRNA) molecule. This enzyme catalyzes the formation of a ester bond between the carboxyl group of L-serine and the 3'-hydroxyl group of the tRNASerine, creating a charged tRNASerine molecule that can participate in protein synthesis on the ribosome.

The systematic name for this enzyme is L-serine:tRNA(Ser) ligase (AMP-forming), and it belongs to the family of ligases, specifically the transfer RNA ligases, which form aminoacyl-tRNA and related compounds. This enzyme is essential for maintaining the accuracy and fidelity of protein synthesis, as it ensures that the correct amino acid is attached to its corresponding tRNA molecule before being translated into a polypeptide chain on the ribosome.

Carbamyl Phosphate is a chemical compound that plays a crucial role in the biochemical process of nitrogen metabolism, particularly in the urea cycle. It is synthesized in the liver and serves as an important intermediate in the conversion of ammonia to urea, which is then excreted by the kidneys.

In medical terms, Carbamyl Phosphate Synthetase I (CPS I) deficiency is a rare genetic disorder that affects the production of Carbamyl Phosphate. This deficiency can lead to hyperammonemia, which is an excess of ammonia in the bloodstream, and can cause severe neurological symptoms and brain damage if left untreated.

It's important to note that while Carbamyl Phosphate is a critical component of the urea cycle, it is not typically used as a medication or therapeutic agent in clinical practice.

Ring finger domains (RFIDs) are a type of protein domain that contain a characteristic cysteine-rich motif. They were initially identified in the RAS-associated proteins called Ras GTPase-activating proteins (GAPs), where they are involved in mediating protein-protein interactions.

The name "ring finger" comes from the fact that these domains contain a series of cysteine and histidine residues that coordinate a central zinc ion, forming a structural ring. This ring is thought to play a role in stabilizing the overall structure of the domain and facilitating its interactions with other proteins.

RFIDs are found in a wide variety of proteins, including transcription factors, chromatin modifiers, and signaling molecules. They have been implicated in a range of cellular processes, including transcriptional regulation, DNA repair, and signal transduction. Mutations in RFID-containing proteins have been linked to various human diseases, including cancer and neurological disorders.

Ribonucleic acid (RNA) is a type of nucleic acid that plays a crucial role in the process of gene expression. There are several types of RNA molecules, including messenger RNA (mRNA), ribosomal RNA (rRNA), and transfer RNA (tRNA). These RNA molecules help to transcribe DNA into mRNA, which is then translated into proteins by the ribosomes.

Fungi are a group of eukaryotic organisms that include microorganisms such as yeasts and molds, as well as larger organisms like mushrooms. Like other eukaryotes, fungi contain DNA and RNA as part of their genetic material. The RNA in fungi is similar to the RNA found in other organisms, including humans, and plays a role in gene expression and protein synthesis.

A specific medical definition of "RNA, fungal" does not exist, as RNA is a fundamental component of all living organisms, including fungi. However, RNA can be used as a target for antifungal drugs, as certain enzymes involved in RNA synthesis and processing are unique to fungi and can be inhibited by these drugs. For example, the antifungal drug flucytosine is converted into a toxic metabolite that inhibits fungal RNA and DNA synthesis.

Cytidine triphosphate (CTP) is a nucleotide that plays a crucial role in the synthesis of RNA. It consists of a cytosine base, a ribose sugar, and three phosphate groups. Cytidine triphosphate is one of the four main building blocks of RNA, along with adenosine triphosphate (ATP), guanosine triphosphate (GTP), and uridine triphosphate (UTP). These nucleotides are essential for various cellular processes, including energy transfer, signal transduction, and biosynthesis. CTP is also involved in the regulation of several metabolic pathways and serves as a cofactor for enzymes that catalyze biochemical reactions. Like other triphosphate nucleotides, CTP provides energy for cellular functions by donating its phosphate groups in energy-consuming processes.

Thiouridine is not a medical term per se, but it is a term used in biochemistry and genetics. Thiouridine is a modified nucleoside that contains a sulfur atom, and it is found in the RNA (ribonucleic acid) of certain organisms, including yeast and mammals.

Thiouridine can be formed through the modification of uridine, one of the four basic building blocks of RNA, by the addition of a sulfur atom from a donor molecule such as cysteine or a derivative thereof. This modification can affect the stability, structure, and function of RNA molecules, including transfer RNAs (tRNAs) and ribosomal RNAs (rRNAs).

In medicine, thiouridine is not used as a therapeutic agent or diagnostic tool, but it may be studied in the context of genetic research or molecular biology.

Transfer RNA (tRNA) that carries the amino acid cysteine (Cys) is a type of adaptor molecule in the process of translation during protein synthesis. The genetic code for cysteine is UGU and UGC, which are the anticodon sequences on specific tRNAs. These tRNA molecules recognize and bind to the corresponding mRNA codons through base-pairing, allowing for the addition of cysteine to the growing polypeptide chain in a ribosome. The tRNA^Cys plays a crucial role in maintaining the fidelity and efficiency of protein synthesis.

Catalysis is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst, which remains unchanged at the end of the reaction. A catalyst lowers the activation energy required for the reaction to occur, thereby allowing the reaction to proceed more quickly and efficiently. This can be particularly important in biological systems, where enzymes act as catalysts to speed up metabolic reactions that are essential for life.

Molecular cloning is a laboratory technique used to create multiple copies of a specific DNA sequence. This process involves several steps:

1. Isolation: The first step in molecular cloning is to isolate the DNA sequence of interest from the rest of the genomic DNA. This can be done using various methods such as PCR (polymerase chain reaction), restriction enzymes, or hybridization.
2. Vector construction: Once the DNA sequence of interest has been isolated, it must be inserted into a vector, which is a small circular DNA molecule that can replicate independently in a host cell. Common vectors used in molecular cloning include plasmids and phages.
3. Transformation: The constructed vector is then introduced into a host cell, usually a bacterial or yeast cell, through a process called transformation. This can be done using various methods such as electroporation or chemical transformation.
4. Selection: After transformation, the host cells are grown in selective media that allow only those cells containing the vector to grow. This ensures that the DNA sequence of interest has been successfully cloned into the vector.
5. Amplification: Once the host cells have been selected, they can be grown in large quantities to amplify the number of copies of the cloned DNA sequence.

Molecular cloning is a powerful tool in molecular biology and has numerous applications, including the production of recombinant proteins, gene therapy, functional analysis of genes, and genetic engineering.

Sequence homology, amino acid, refers to the similarity in the order of amino acids in a protein or a portion of a protein between two or more species. This similarity can be used to infer evolutionary relationships and functional similarities between proteins. The higher the degree of sequence homology, the more likely it is that the proteins are related and have similar functions. Sequence homology can be determined through various methods such as pairwise alignment or multiple sequence alignment, which compare the sequences and calculate a score based on the number and type of matching amino acids.

Glutamic acid is an alpha-amino acid, which is one of the 20 standard amino acids in the genetic code. The systematic name for this amino acid is (2S)-2-Aminopentanedioic acid. Its chemical formula is HO2CCH(NH2)CH2CH2CO2H.

Glutamic acid is a crucial excitatory neurotransmitter in the human brain, and it plays an essential role in learning and memory. It's also involved in the metabolism of sugars and amino acids, the synthesis of proteins, and the removal of waste nitrogen from the body.

Glutamic acid can be found in various foods such as meat, fish, beans, eggs, dairy products, and vegetables. In the human body, glutamic acid can be converted into gamma-aminobutyric acid (GABA), another important neurotransmitter that has a calming effect on the nervous system.

Dihydroorotase is an enzyme that plays a crucial role in the synthesis of pyrimidines, which are essential components of nucleic acids such as DNA and RNA. Specifically, dihydroorotase catalyzes the conversion of N-carbamoyl-L-aspartate into L-dihydroorotate and L-carbamoyl aspartate in the third step of de novo pyrimidine biosynthesis.

The reaction catalyzed by dihydroorotase is:

N-carbamoyl-L-aspartate + H2O → L-dihydroorotate + L-carbamoyl aspartate

Dihydroorotase is a member of the amidohydrolase superfamily and functions as a homodimer or homotetramer. In humans, dihydroorotase is encoded by the DHODH gene and is found in the cytoplasm of cells. Defects in this enzyme can lead to a rare genetic disorder called dihydropyrimidine dehydrogenase deficiency, which is characterized by an accumulation of pyrimidines and their precursors in the body.

Aspartate-tRNA ligase is an enzyme that plays a crucial role in protein synthesis. Its specific function is to join the amino acid aspartic acid to its corresponding transfer RNA (tRNA) molecule, forming an aspartyl-tRNA complex. This complex is essential for the accurate translation of genetic information encoded in messenger RNA (mRNA) into a polypeptide chain during protein synthesis.

The systematic name for this enzyme is L-aspartate:tRNA(Asn) ligase (AMP-forming), which reflects its role in catalyzing the reaction between aspartic acid and tRNA(Asn). The enzyme can also activate aspartic acid by forming an aspartyl-AMP intermediate before transferring the activated aspartate to the appropriate tRNA molecule.

Deficiencies or mutations in aspartate-tRNA ligase can lead to various genetic disorders and impairments in protein synthesis, which may have severe consequences for cellular function and overall health.

Protein biosynthesis is the process by which cells generate new proteins. It involves two major steps: transcription and translation. Transcription is the process of creating a complementary RNA copy of a sequence of DNA. This RNA copy, or messenger RNA (mRNA), carries the genetic information to the site of protein synthesis, the ribosome. During translation, the mRNA is read by transfer RNA (tRNA) molecules, which bring specific amino acids to the ribosome based on the sequence of nucleotides in the mRNA. The ribosome then links these amino acids together in the correct order to form a polypeptide chain, which may then fold into a functional protein. Protein biosynthesis is essential for the growth and maintenance of all living organisms.

Glutamine is defined as a conditionally essential amino acid in humans, which means that it can be produced by the body under normal circumstances, but may become essential during certain conditions such as stress, illness, or injury. It is the most abundant free amino acid found in the blood and in the muscles of the body.

Glutamine plays a crucial role in various biological processes, including protein synthesis, energy production, and acid-base balance. It serves as an important fuel source for cells in the intestines, immune system, and skeletal muscles. Glutamine has also been shown to have potential benefits in wound healing, gut function, and immunity, particularly during times of physiological stress or illness.

In summary, glutamine is a vital amino acid that plays a critical role in maintaining the health and function of various tissues and organs in the body.

Genetic suppression is a concept in genetics that refers to the phenomenon where the expression or function of one gene is reduced or silenced by another gene. This can occur through various mechanisms such as:

* Allelic exclusion: When only one allele (version) of a gene is expressed, while the other is suppressed.
* Epigenetic modifications: Chemical changes to the DNA or histone proteins that package DNA can result in the suppression of gene expression.
* RNA interference: Small RNAs can bind to and degrade specific mRNAs (messenger RNAs), preventing their translation into proteins.
* Transcriptional repression: Proteins called transcription factors can bind to DNA and prevent the recruitment of RNA polymerase, which is necessary for gene transcription.

Genetic suppression plays a crucial role in regulating gene expression and maintaining proper cellular function. It can also contribute to diseases such as cancer when genes that suppress tumor growth are suppressed themselves.

The liver is a large, solid organ located in the upper right portion of the abdomen, beneath the diaphragm and above the stomach. It plays a vital role in several bodily functions, including:

1. Metabolism: The liver helps to metabolize carbohydrates, fats, and proteins from the food we eat into energy and nutrients that our bodies can use.
2. Detoxification: The liver detoxifies harmful substances in the body by breaking them down into less toxic forms or excreting them through bile.
3. Synthesis: The liver synthesizes important proteins, such as albumin and clotting factors, that are necessary for proper bodily function.
4. Storage: The liver stores glucose, vitamins, and minerals that can be released when the body needs them.
5. Bile production: The liver produces bile, a digestive juice that helps to break down fats in the small intestine.
6. Immune function: The liver plays a role in the immune system by filtering out bacteria and other harmful substances from the blood.

Overall, the liver is an essential organ that plays a critical role in maintaining overall health and well-being.

The proteasome endopeptidase complex is a large protein complex found in the cells of eukaryotic organisms, as well as in archaea and some bacteria. It plays a crucial role in the degradation of damaged or unneeded proteins through a process called proteolysis. The proteasome complex contains multiple subunits, including both regulatory and catalytic particles.

The catalytic core of the proteasome is composed of four stacked rings, each containing seven subunits, forming a structure known as the 20S core particle. Three of these rings are made up of beta-subunits that contain the proteolytic active sites, while the fourth ring consists of alpha-subunits that control access to the interior of the complex.

The regulatory particles, called 19S or 11S regulators, cap the ends of the 20S core particle and are responsible for recognizing, unfolding, and translocating targeted proteins into the catalytic chamber. The proteasome endopeptidase complex can cleave peptide bonds in various ways, including hydrolysis of ubiquitinated proteins, which is an essential mechanism for maintaining protein quality control and regulating numerous cellular processes, such as cell cycle progression, signal transduction, and stress response.

In summary, the proteasome endopeptidase complex is a crucial intracellular machinery responsible for targeted protein degradation through proteolysis, contributing to various essential regulatory functions in cells.

Protein conformation refers to the specific three-dimensional shape that a protein molecule assumes due to the spatial arrangement of its constituent amino acid residues and their associated chemical groups. This complex structure is determined by several factors, including covalent bonds (disulfide bridges), hydrogen bonds, van der Waals forces, and ionic bonds, which help stabilize the protein's unique conformation.

Protein conformations can be broadly classified into two categories: primary, secondary, tertiary, and quaternary structures. The primary structure represents the linear sequence of amino acids in a polypeptide chain. The secondary structure arises from local interactions between adjacent amino acid residues, leading to the formation of recurring motifs such as α-helices and β-sheets. Tertiary structure refers to the overall three-dimensional folding pattern of a single polypeptide chain, while quaternary structure describes the spatial arrangement of multiple folded polypeptide chains (subunits) that interact to form a functional protein complex.

Understanding protein conformation is crucial for elucidating protein function, as the specific three-dimensional shape of a protein directly influences its ability to interact with other molecules, such as ligands, nucleic acids, or other proteins. Any alterations in protein conformation due to genetic mutations, environmental factors, or chemical modifications can lead to loss of function, misfolding, aggregation, and disease states like neurodegenerative disorders and cancer.

Alanine is an alpha-amino acid that is used in the biosynthesis of proteins. The molecular formula for alanine is C3H7NO2. It is a non-essential amino acid, which means that it can be produced by the human body through the conversion of other nutrients, such as pyruvate, and does not need to be obtained directly from the diet.

Alanine is classified as an aliphatic amino acid because it contains a simple carbon side chain. It is also a non-polar amino acid, which means that it is hydrophobic and tends to repel water. Alanine plays a role in the metabolism of glucose and helps to regulate blood sugar levels. It is also involved in the transfer of nitrogen between tissues and helps to maintain the balance of nitrogen in the body.

In addition to its role as a building block of proteins, alanine is also used as a neurotransmitter in the brain and has been shown to have a calming effect on the nervous system. It is found in many foods, including meats, poultry, fish, eggs, dairy products, and legumes.

In genetics, sequence alignment is the process of arranging two or more DNA, RNA, or protein sequences to identify regions of similarity or homology between them. This is often done using computational methods to compare the nucleotide or amino acid sequences and identify matching patterns, which can provide insight into evolutionary relationships, functional domains, or potential genetic disorders. The alignment process typically involves adjusting gaps and mismatches in the sequences to maximize the similarity between them, resulting in an aligned sequence that can be visually represented and analyzed.

Ribosomes are complex macromolecular structures composed of ribonucleic acid (RNA) and proteins that play a crucial role in protein synthesis within cells. They serve as the site for translation, where messenger RNA (mRNA) is translated into a specific sequence of amino acids to create a polypeptide chain, which eventually folds into a functional protein.

Ribosomes consist of two subunits: a smaller subunit and a larger subunit. These subunits are composed of ribosomal RNA (rRNA) molecules and proteins. In eukaryotic cells, the smaller subunit is denoted as the 40S subunit, while the larger subunit is referred to as the 60S subunit. In prokaryotic cells, these subunits are named the 30S and 50S subunits, respectively. The ribosome's overall structure resembles a "doughnut" or a "cotton reel," with grooves and binding sites for various factors involved in protein synthesis.

Ribosomes can be found floating freely within the cytoplasm of cells or attached to the endoplasmic reticulum (ER) membrane, forming part of the rough ER. Membrane-bound ribosomes are responsible for synthesizing proteins that will be transported across the ER and ultimately secreted from the cell or inserted into the membrane. In contrast, cytoplasmic ribosomes synthesize proteins destined for use within the cytoplasm or organelles.

In summary, ribosomes are essential components of cells that facilitate protein synthesis by translating mRNA into functional polypeptide chains. They can be found in various cellular locations and exist as either free-floating entities or membrane-bound structures.

Transfer RNA (tRNA) that carries asparagine (Asn) is a type of RNA molecule that plays a crucial role in protein synthesis. Specifically, tRNAs are responsible for delivering the appropriate amino acids to the ribosome during translation, the process by which genetic information encoded in messenger RNA (mRNA) is translated into proteins.

In the case of tRNA-Asn, this RNA molecule carries the amino acid asparagine, which is one of the 20 standard amino acids used to build proteins. The tRNA-Asn molecule recognizes a specific codon (a sequence of three nucleotides) in the mRNA that corresponds to asparagine, and then brings the appropriate amino acid to the ribosome to be incorporated into the growing polypeptide chain.

The correct pairing of tRNAs with their corresponding codons is facilitated by anticodon loops present on the tRNA molecules, which contain complementary sequences to the codons in the mRNA. In the case of tRNA-Asn, the anticodon loop contains the sequence UGU, which is complementary to the asparagine codons AAU and AAC in the mRNA.

Overall, tRNAs like tRNA-Asn are essential for the accurate and efficient synthesis of proteins in all living organisms.

Genetic transcription is the process by which the information in a strand of DNA is used to create a complementary RNA molecule. This process is the first step in gene expression, where the genetic code in DNA is converted into a form that can be used to produce proteins or functional RNAs.

During transcription, an enzyme called RNA polymerase binds to the DNA template strand and reads the sequence of nucleotide bases. As it moves along the template, it adds complementary RNA nucleotides to the growing RNA chain, creating a single-stranded RNA molecule that is complementary to the DNA template strand. Once transcription is complete, the RNA molecule may undergo further processing before it can be translated into protein or perform its functional role in the cell.

Transcription can be either "constitutive" or "regulated." Constitutive transcription occurs at a relatively constant rate and produces essential proteins that are required for basic cellular functions. Regulated transcription, on the other hand, is subject to control by various intracellular and extracellular signals, allowing cells to respond to changing environmental conditions or developmental cues.

Lysine is an essential amino acid, which means that it cannot be synthesized by the human body and must be obtained through the diet. Its chemical formula is (2S)-2,6-diaminohexanoic acid. Lysine is necessary for the growth and maintenance of tissues in the body, and it plays a crucial role in the production of enzymes, hormones, and antibodies. It is also essential for the absorption of calcium and the formation of collagen, which is an important component of bones and connective tissue. Foods that are good sources of lysine include meat, poultry, fish, eggs, and dairy products.

A cell line is a culture of cells that are grown in a laboratory for use in research. These cells are usually taken from a single cell or group of cells, and they are able to divide and grow continuously in the lab. Cell lines can come from many different sources, including animals, plants, and humans. They are often used in scientific research to study cellular processes, disease mechanisms, and to test new drugs or treatments. Some common types of human cell lines include HeLa cells (which come from a cancer patient named Henrietta Lacks), HEK293 cells (which come from embryonic kidney cells), and HUVEC cells (which come from umbilical vein endothelial cells). It is important to note that cell lines are not the same as primary cells, which are cells that are taken directly from a living organism and have not been grown in the lab.

Pyridoxal phosphate (PLP) is the active form of vitamin B6 and functions as a cofactor in various enzymatic reactions in the human body. It plays a crucial role in the metabolism of amino acids, carbohydrates, lipids, and neurotransmitters. Pyridoxal phosphate is involved in more than 140 different enzyme-catalyzed reactions, making it one of the most versatile cofactors in human biochemistry.

As a cofactor, pyridoxal phosphate helps enzymes carry out their functions by facilitating chemical transformations in substrates (the molecules on which enzymes act). In particular, PLP is essential for transamination, decarboxylation, racemization, and elimination reactions involving amino acids. These processes are vital for the synthesis and degradation of amino acids, neurotransmitters, hemoglobin, and other crucial molecules in the body.

Pyridoxal phosphate is formed from the conversion of pyridoxal (a form of vitamin B6) by the enzyme pyridoxal kinase, using ATP as a phosphate donor. The human body obtains vitamin B6 through dietary sources such as whole grains, legumes, vegetables, nuts, and animal products like poultry, fish, and pork. It is essential to maintain adequate levels of pyridoxal phosphate for optimal enzymatic function and overall health.

A plasmid is a small, circular, double-stranded DNA molecule that is separate from the chromosomal DNA of a bacterium or other organism. Plasmids are typically not essential for the survival of the organism, but they can confer beneficial traits such as antibiotic resistance or the ability to degrade certain types of pollutants.

Plasmids are capable of replicating independently of the chromosomal DNA and can be transferred between bacteria through a process called conjugation. They often contain genes that provide resistance to antibiotics, heavy metals, and other environmental stressors. Plasmids have also been engineered for use in molecular biology as cloning vectors, allowing scientists to replicate and manipulate specific DNA sequences.

Plasmids are important tools in genetic engineering and biotechnology because they can be easily manipulated and transferred between organisms. They have been used to produce vaccines, diagnostic tests, and genetically modified organisms (GMOs) for various applications, including agriculture, medicine, and industry.

X-ray crystallography is a technique used in structural biology to determine the three-dimensional arrangement of atoms in a crystal lattice. In this method, a beam of X-rays is directed at a crystal and diffracts, or spreads out, into a pattern of spots called reflections. The intensity and angle of each reflection are measured and used to create an electron density map, which reveals the position and type of atoms in the crystal. This information can be used to determine the molecular structure of a compound, including its shape, size, and chemical bonds. X-ray crystallography is a powerful tool for understanding the structure and function of biological macromolecules such as proteins and nucleic acids.

Post-transcriptional RNA processing refers to the modifications and regulations that occur on RNA molecules after the transcription of DNA into RNA. This process includes several steps:

1. 5' capping: The addition of a cap structure, usually a methylated guanosine triphosphate (GTP), to the 5' end of the RNA molecule. This helps protect the RNA from degradation and plays a role in its transport, stability, and translation.
2. 3' polyadenylation: The addition of a string of adenosine residues (poly(A) tail) to the 3' end of the RNA molecule. This process is important for mRNA stability, export from the nucleus, and translation initiation.
3. Intron removal and exon ligation: Eukaryotic pre-messenger RNAs (pre-mRNAs) contain intronic sequences that do not code for proteins. These introns are removed by a process called splicing, where the flanking exons are joined together to form a continuous mRNA sequence. Alternative splicing can lead to different mature mRNAs from a single pre-mRNA, increasing transcriptomic and proteomic diversity.
4. RNA editing: Specific nucleotide changes in RNA molecules that alter the coding potential or regulatory functions of RNA. This process is catalyzed by enzymes like ADAR (Adenosine Deaminases Acting on RNA) and APOBEC (Apolipoprotein B mRNA Editing Catalytic Polypeptide-like).
5. Chemical modifications: Various chemical modifications can occur on RNA nucleotides, such as methylation, pseudouridination, and isomerization. These modifications can influence RNA stability, localization, and interaction with proteins or other RNAs.
6. Transport and localization: Mature mRNAs are transported from the nucleus to the cytoplasm for translation. In some cases, specific mRNAs are localized to particular cellular compartments to ensure local protein synthesis.
7. Degradation: RNA molecules have finite lifetimes and undergo degradation by various ribonucleases (RNases). The rate of degradation can be influenced by factors such as RNA structure, modifications, or interactions with proteins.

A Structure-Activity Relationship (SAR) in the context of medicinal chemistry and pharmacology refers to the relationship between the chemical structure of a drug or molecule and its biological activity or effect on a target protein, cell, or organism. SAR studies aim to identify patterns and correlations between structural features of a compound and its ability to interact with a specific biological target, leading to a desired therapeutic response or undesired side effects.

By analyzing the SAR, researchers can optimize the chemical structure of lead compounds to enhance their potency, selectivity, safety, and pharmacokinetic properties, ultimately guiding the design and development of novel drugs with improved efficacy and reduced toxicity.

Bacterial proteins are a type of protein that are produced by bacteria as part of their structural or functional components. These proteins can be involved in various cellular processes, such as metabolism, DNA replication, transcription, and translation. They can also play a role in bacterial pathogenesis, helping the bacteria to evade the host's immune system, acquire nutrients, and multiply within the host.

Bacterial proteins can be classified into different categories based on their function, such as:

1. Enzymes: Proteins that catalyze chemical reactions in the bacterial cell.
2. Structural proteins: Proteins that provide structural support and maintain the shape of the bacterial cell.
3. Signaling proteins: Proteins that help bacteria to communicate with each other and coordinate their behavior.
4. Transport proteins: Proteins that facilitate the movement of molecules across the bacterial cell membrane.
5. Toxins: Proteins that are produced by pathogenic bacteria to damage host cells and promote infection.
6. Surface proteins: Proteins that are located on the surface of the bacterial cell and interact with the environment or host cells.

Understanding the structure and function of bacterial proteins is important for developing new antibiotics, vaccines, and other therapeutic strategies to combat bacterial infections.

In enzymology, an aspartate-tRNA ligase (EC 6.1.1.12) is an enzyme that catalyzes the chemical reaction ATP + L-aspartate + ... L-aspartate, and tRNA(Asp), whereas its 3 products are AMP, diphosphate, and L-aspartyl-tRNA(Asp). This enzyme belongs to the ... The systematic name of this enzyme class is L-aspartate:tRNAAsp ligase (AMP-forming). Other names in common use include ... This enzyme participates in alanine and aspartate metabolism and aminoacyl-trna biosynthesis. As of late 2007, 10 structures ...
Aspartate-tRNAAsn ligase (EC 6.1.1.23, nondiscriminating aspartyl-tRNA synthetase) is an enzyme with systematic name L- ... When this enzyme acts on tRNAAsp, it catalyses the same reaction as EC 6.1.1.12, aspartate---tRNA ligase. It has, however, ... aspartate:tRNAAsx ligase (AMP-forming). This enzyme catalyses the following chemical reaction ATP + L-aspartate + tRNAAsx ⇌ {\ ... This enzyme belongs to the family of ligases, to be specific those forming carbon-oxygen bonds in aminoacyl-tRNA and related ...
Aspartate-tRNA ligase GRCh38: Ensembl release 89: ENSG00000115866 - Ensembl, May 2017 GRCm38: Ensembl release 89: ... Aspartyl-tRNA synthetase charges its cognate tRNA with aspartate during protein biosynthesis. Mutations in DARS have been ... Aspartyl-tRNA synthetase, cytoplasmic is an enzyme that in humans is encoded by the DARS gene. Aspartyl-tRNA synthetase (DARS) ... Reed VS, Wastney ME, Yang DC (1995). "Mechanisms of the transfer of aminoacyl-tRNA from aminoacyl-tRNA synthetase to the ...
... that are uniquely present in this genus in the proteins aspartate-tRNA ligase, A/G-specific adenine glycosylase, thymidylate ...
... and Ala-tRNA synthetase. This enzyme participates in alanine and aspartate metabolism and aminoacyl-trna biosynthesis. Sticky ... In enzymology, an alanine-tRNA ligase (EC 6.1.1.7) is an enzyme that catalyzes the chemical reaction ATP + L-alanine + tRNAAla ... and L-alanyl-tRNA(Ala). This enzyme belongs to the family of ligases, to be specific those forming carbon-oxygen bonds in ... alanine-transfer RNA ligase, alanine transfer RNA synthetase, alanine tRNA synthetase, alanine translase, alanyl-transfer ...
This enzyme participates in alanine and aspartate metabolism and aminoacyl-trna biosynthesis. As of late 2007, 3 structures ... In enzymology, an asparagine-tRNA ligase (EC 6.1.1.22) is an enzyme that catalyzes the chemical reaction ATP + L-asparagine + ... and L-asparaginyl-tRNA(Asn). This enzyme belongs to the family of ligases, to be specific those forming carbon-oxygen bonds in ... aminoacyl-tRNA and related compounds. The systematic name of this enzyme class is L-asparagine:tRNAAsn ligase (AMP-forming). ...
... alanine-tRNA ligase MeSH D08.811.464.263.200.100 - arginine-tRNA ligase MeSH D08.811.464.263.200.150 - aspartate-tRNA ligase ... glutamate-trna ligase MeSH D08.811.464.263.200.350 - glycine-trna ligase MeSH D08.811.464.263.200.400 - histidine-trna ligase ... isoleucine-trna ligase MeSH D08.811.464.263.200.500 - leucine-trna ligase MeSH D08.811.464.263.200.550 - lysine-trna ligase ... serine-trna ligase MeSH D08.811.464.263.200.800 - threonine-tRNA ligase MeSH D08.811.464.263.200.850 - tryptophan-tRNA ligase ...
This enzyme belongs to the family of ligases, specifically those forming carbon-nitrogen bonds carbon-nitrogen ligases with ... This enzyme participates in glutamate metabolism and alanine and aspartate metabolism. Min B, Pelaschier JT, Graham DE, Tumbula ... aspartyl-tRNA(Asn), and L-glutamine, whereas its 4 products are ADP, phosphate, asparaginyl-tRNA(Asn), and L-glutamate. ... In enzymology, an asparaginyl-tRNA synthase (glutamine-hydrolysing) (EC 6.3.5.6) is an enzyme that catalyzes the chemical ...
This enzyme belongs to the family of ligases, specifically those forming carbon-nitrogen bonds carbon-nitrogen ligases with ... This enzyme participates in glutamate metabolism and alanine and aspartate metabolism. Horiuchi KY, Harpel MR, Shen L, Luo Y, ... glutamyl-tRNA(Gln), and L-glutamine, whereas its 4 products are ADP, phosphate, glutaminyl-tRNA(Gln), and L-glutamate. ... Ibba M, Soll D (2000). "Aminoacyl-tRNA synthesis". Annu. Rev. Biochem. 69: 617-50. doi:10.1146/annurev.biochem.69.1.617. PMID ...
... valine-tRNA ligase EC 6.1.1.10: methionine-tRNA ligase EC 6.1.1.11: serine-tRNA ligase EC 6.1.1.12: aspartate-tRNA ligase EC ... threonine-tRNA ligase EC 6.1.1.4: leucine-tRNA ligase EC 6.1.1.5: isoleucine-tRNA ligase EC 6.1.1.6: lysine-tRNA ligase EC 6.1. ... glycine-tRNA ligase EC 6.1.1.15: proline-tRNA ligase EC 6.1.1.16: cysteine-tRNA ligase EC 6.1.1.17: glutamate-tRNA ligase EC ... phenylalanine-tRNA ligase EC 6.1.1.21: histidine-tRNA ligase EC 6.1.1.22: asparagine-tRNA ligase EC 6.1.1.23: aspartate-tRNAAsn ...
... glutamate-tRNA ligase, EC 1.2.1.70, glutamyl-tRNA reductase and EC 5.4.3.8 glutamate-1-semialdehyde 2,1-aminomutase EC 2.7.2.14 ... tRNA-5-methyluridine54 2-sulfurtransferase (*) EC 2.8.1.16: L-aspartate semialdehyde sulfurtransferase (*) (*) No Wikipedia ... tRNA (guanine46-N7)-methyltransferase EC 2.1.1.34: tRNA (guanosine18-2′-O)-methyltransferase EC 2.1.1.35: tRNA (uracil54-C5)- ... tRNA (guanine110-N2)-dimethyltransferase EC 2.1.1.214: tRNA (guanine10-N2)-methyltransferase EC 2.1.1.215: tRNA (guanine26-N2/ ...
... ubiquitin protein ligase E3 component n-recognin 2 (6p21.2) UNC5CL: encoding protein Unc-5 homolog C (C. elegans)-like USP8P1: ... D-aspartate) O-methyltransferase (6q25.1) PERP: p53 apoptosis effector related to PMP-22 (6q23.3) PKIB: cAMP-dependent protein ... "genetype trna"[Properties] OR "genetype scrna"[Properties] OR "genetype snrna"[Properties] OR "genetype snorna"[Properties]) ... E3 ubiquitin protein ligase 1 (6q21) HEBP2: heme binding protein 2 (6q24.1) IDDM8: insulin dependent diabetes mellitus 8 IDDM15 ...
DNA polymerase and DNA ligase then completes the process by incorporating the correct base pair and closing the nick. The UDG ... Hydrogen bonding between water and aspartate prepares the water molecule for nucleophilic attack of the N-glycosidic bond, ... is a naturally-occurring base in human tRNA or in wobble base pairing, it is mistakenly incorporated into DNA either through ...
... aspartate 4-decarboxylase EC 4.1.1.11: aspartate 1-decarboxylase EC 4.1.1.12: aspartate 4-decarboxylase EC 4.1.1.13: deleted EC ... tRNA-intron lyase EC 4.6.1.17: cyclic pyranopterin monophosphate synthase * EC 4.6.1.18: pancreatic ribonuclease * EC 4.6.1.19 ... heme ligase EC 4.99.1.9:: coproporphyrin ferrochelatase * EC 4.99.1.10: magnesium dechelatase * EC 4.99.1.11: sirohydrochlorin ... 3-hydroxy-D-aspartate aldolase EC 4.1.3.42: (4S)-4-hydroxy-2-oxoglutarate aldolase * EC 4.1.3.43: 4-hydroxy-2-oxohexanoate ...
This entry comprises bacterial enzymes that import Histidine, Arginine, Lysine, Glutamine, Glutamate, Aspartate, ornithine, ... and ligases (EC 6). However, it became apparent that none of these could describe the important group of enzymes that catalyse ... tRNA) and messenger RNA (mRNA) through the ribosome. The enzyme classification and nomenclature list was first approved by the ...
... tRNA ↽ − − ⇀ aminoacyl − tRNA + AMP {\displaystyle {\ce {{Aminoacyl-AMP}+ tRNA <=> {aminoacyl-tRNA}+ AMP}}} The combination of ... The biosynthesis of aspartate is a one step reaction that is catalyzed by a single enzyme. The enzyme aspartate ... Okazaki fragments are covalently joined by DNA ligase to form a continuous strand. Then, to complete DNA replication, RNA ... This reaction, called tRNA charging, is catalyzed by aminoacyl tRNA synthetase. A specific tRNA synthetase is responsible for ...
Mitochondrial tRNA genes have different sequences from the nuclear tRNAs, but lookalikes of mitochondrial tRNAs have been found ... Reducing equivalents from the cytoplasm can be imported via the malate-aspartate shuttle system of antiporter proteins or fed ... kynurenine hydroxylase and fatty acid Co-A ligase. Disruption of the outer membrane permits proteins in the intermembrane space ... It encodes 37 genes: 13 for subunits of respiratory complexes I, III, IV and V, 22 for mitochondrial tRNA (for the 20 standard ...
Glutarate-CoA ligase EC 6.2.1.7: Cholate-CoA ligase EC 6.2.1.8: Oxalate-CoA ligase EC 6.2.1.9: Malate-CoA ligase EC 6.2.1.10: ... L-seryl-tRNA(Sec) selenium transferase EC 2.9.1.2: O-phospho-L-seryl-tRNA(Sec):L-selenocysteinyl-tRNA synthase Hydrolytic ... EC 2.1.3 Aspartate transcarbamoylase EC 2.1.3.2 Ornithine transcarbamoylase EC 2.1.3.3 Category:EC 2.2.1 Transketolase EC 2.2. ... ligase EC 6.2.1.23: Dicarboxylate-CoA ligase EC 6.2.1.24: Phytanate-CoA ligase EC 6.2.1.25: Benzoate-CoA ligase EC 6.2.1.26: o- ...
... tRNA(adenine34) deaminase * EC 3.5.4.34: tRNAAla(adenine37) deaminase * EC 3.5.4.35: tRNA(cytosine8) deaminase * EC 3.5.4.36: ... N-acyl-D-aspartate deacylase EC 3.5.1.84: biuret amidohydrolase EC 3.5.1.85: (S)-N-acetyl-1-phenylethylamine hydrolase EC 3.5. ... glutamateammonia ligase] phosphorylase EC 3.1.4.16: 2′,3′-cyclic-nucleotide 2′-phosphodiesterase EC 3.1.4.17: 3′,5′-cyclic- ... tRNA-intron lyase EC 3.1.27.10: Now EC 4.6.1.23, ribotoxin, EC 3.1.30.1: Aspergillus nuclease S1 EC 3.1.30.2: Serratia ...
In enzymology, an aspartate-tRNA ligase (EC 6.1.1.12) is an enzyme that catalyzes the chemical reaction ATP + L-aspartate + ... L-aspartate, and tRNA(Asp), whereas its 3 products are AMP, diphosphate, and L-aspartyl-tRNA(Asp). This enzyme belongs to the ... The systematic name of this enzyme class is L-aspartate:tRNAAsp ligase (AMP-forming). Other names in common use include ... This enzyme participates in alanine and aspartate metabolism and aminoacyl-trna biosynthesis. As of late 2007, 10 structures ...
aspartate--tRNA ligase 3680 R. AspP4MrrP (100% identity) AspP3MrrP. 3685 dihydroneopterin triphosphate diphosphatase ...
The DARS2 gene provides instructions for making an enzyme called mitochondrial aspartyl-tRNA synthetase. Learn about this gene ... aspartate tRNA ligase 2, mitochondrial. *aspartyl-tRNA synthetase, mitochondrial. *aspartyl-tRNA synthetase, mitochondrial ... Mitochondrial aspartyl-tRNA synthetase attaches the amino acid aspartic acid to the correct tRNA, which helps ensure that ... Each tRNA carries a specific amino acid to the growing chain. Enzymes called aminoacyl-tRNA synthetases, including ...
... glutamine-tRNA ligase and cytoplasmic aspartate-tRNA ligase were among the significantly increased proteins, as was a component ... cytoplasmic aspartate aminotransferase) (Table S4), which might reflect changes in glutamine and aspartate metabolism. ...
Full Name: Aspartate--tRNA ligase, mitochondrial O-GlcNAc Score: 1 References 0 O-GlcNAc sites ...
Align Aspartate--tRNA(Asp/Asn) ligase; Aspartyl-tRNA synthetase; AspRS; Non-discriminating aspartyl-tRNA synthetase; ND-AspRS; ... to candidate Dsui_1315 Dsui_1315 aspartyl-tRNA synthetase. Query= SwissProt::Q51422 (591 letters) >FitnessBrowser__PS:Dsui_1315 ...
Aspartate-tRNA Ligase Medicine & Life Sciences 100% * RNA, Transfer, Asp Medicine & Life Sciences 96% ... Biochemical and Structural Characterization of Mycobacterial Aspartyl-tRNA Final published version, 6.43 MBLicence: CC BY 3.0 ... 2014). Biochemical and structural characterization of mycobacterial aspartyl-tRNA synthetase AspS, a promising TB drug target. ... Biochemical and structural characterization of mycobacterial aspartyl-tRNA synthetase AspS, a promising TB drug target. In: ...
","aspartate--tRNA ligase [Ensembl]. GAD domain, tRNA synthetases class II (D, OB-fold nucleic acid binding domain [ ... tRNA ligase [Ensembl]. Leucyl-tRNA synthetase, tRNA synthetases class I (I, tRNA synthetases class I (M), Anticodon-binding ... tRNA ligase) (valine translase) [Ensembl]. tRNA synthetases class I (I, Anticodon-binding domain of tRNA, Valyl tRNA synthetase ... tRNA ligase [Ensembl]. Putative tRNA binding domain, tRNA synthetases class I (M), Anticodon-binding domain of tRNA [ ...
Aspartate--tRNA ligase, cytoplasmic [Source:UniProtKB/Swiss-Prot;Acc:Q03577]. 84.. T05G5.10. iff-1. 42569. 7.556. 0.943. 0.957 ...
tRNA-specific 2-thiouridylase MnmA. NP_390627.3. BBF10K_000950. aspS. aspartate--tRNA ligase. NP_390633.1. BBF10K_000951. ... glycine--tRNA ligase beta subunit. NP_390404.2. BBF10K_000942. glyQ. glycine--tRNA ligase alpha subunit. NP_390405.1. BBF10K_ ... phenylalanine--tRNA ligase beta subunit. NP_390741.1. BBF10K_000967. pheS. phenylalanine--tRNA ligase alpha subunit. NP_ ... methionine--tRNA ligase. NP_387919.1. BBF10K_000757. ipk. 4-diphosphocytidyl-2C-methyl-D-erythritolkinase. NP_387927.1. BBF10K_ ...
","aspartate--tRNA ligase [Ensembl]. tRNA synthetases class II (D, OB-fold nucleic acid binding domain [Interproscan]."," ... ","glycyl-tRNA synthetase, alpha subunit [Ensembl]. Glycine-tRNA ligase [Interproscan].","protein_coding" "AKI49477","rpsT"," ... ","D-alanine-D-alanine ligase A [Ensembl]. D-ala D-ala ligase C-terminus, D-ala D-ala ligase N-terminus [Interproscan]."," ... ","tRNA m(1)G37 methyltransferase, SAM-dependent [Ensembl]. tRNA (Guanine-1)-methyltransferase [Interproscan].","protein_coding ...
tRNA synthetase class II (D, K and N) family protein. F:aspartate-tRNA ligase activity, nucleotide binding, aminoacyl-tRNA ... ligase activity, nucleic acid binding, ATP binding;P:aspartyl-tRNA aminoacylation, translation, tRNA aminoacylation for protein ...
6.1.1.12Name: aspartate---tRNA ligase. Other names: aspartyl-tRNA synthetase, aspartyl ribonucleic synthetase, aspartyl- ... 6.1.1.12Name: aspartate---tRNA ligase. Other names: aspartyl-tRNA synthetase, aspartyl ribonucleic synthetase, aspartyl- ... RC05577Name: L-Aspartate:tRNA(Asp) ligase (AMP-forming). Type: Regular. Location: Cytosol. KEGG ID: R05577. click to see ... RM05577Name: L-Aspartate:tRNA(Asp) ligase (AMP-forming). Type: Regular. Location: Mitochondria. KEGG ID: R05577. click to see ...
Aspartate-tRNA Ligase Activity. *Protein Binding. *ATP Binding. Biological Process. *Translation. *TRNA Aminoacylation For ...
Aspartate-tRNA Ligase Activity. *Protein Binding. *ATP Binding. *Poly(A) RNA Binding ...
aspartyl-tRNA synthetase. -. 7e-5. At4g31180. aspartyl-tRNA synthetase, putative / aspartate--tRNA ligase, putative. O.I.. H.G. ...
... and asparagine-tRNA ligase (6.1.1.22) were also present with 3.2 and 9.2% of abundance, respectively. Among the total of genes ... involved in the conversion of L-asparagine to aspartate was found. ... Glutamyl-tRNA reductase (1.2.1.70), encoded by another enriched gene at T1, makes up the first part of the metabolic pathway ... In addition, 1 gene encoding a ligase from the metabolism of lipoic acid was also evidenced. Thiamine and lipoic acid are ...
Aspartate. aminotransferase,. cytoplasmic. Nitric oxide. synthase, brain. Bifunctional. glutamate/proline-. -tRNA ligase. ... tRNA(Arg). L-Arginyl-. tRNA(Arg). tRNA(Pro). L-Prolyl-. tRNA(Pro). Citric Acid. Cycle. Alanine. Metabolism. D-Arginine and. D- ... arginine--tRNA. ligase,. mitochondrial. Glycine. amidinotransferase,. mitochondrial. Guanidinoacetate. N-. methyltransferase. ...
Aspartate. aminotransferase,. cytoplasmic. Nitric oxide. synthase, brain. Bifunctional. glutamate/proline-. -tRNA ligase. ... tRNA(Arg). L-Arginyl-. tRNA(Arg). tRNA(Pro). L-Prolyl-. tRNA(Pro). Citric Acid. Cycle. Alanine. Metabolism. D-Arginine and. D- ... arginine--tRNA. ligase,. mitochondrial. Glycine. amidinotransferase,. mitochondrial. Guanidinoacetate. N-. methyltransferase. ...
Aspartate. aminotransferase,. mitochondrial. Glutamyl-tRNA. synthetase 2,. mitochondrial. Glutamate--. cysteine ligase. ... tRNA(Glu). L-Glutamyl-. tRNA(Glu). tRNA(Gln). L-Glutaminyl-. tRNA(Gln). Glutathione. Metabolism. Pyrimidine. Metabolism. Purine ... Glutamine--tRNA. ligase. L-Glutamic acid. Carbamoyl phosphate. 5-Phosphoribosylamine. γ-Aminobutyric acid. 1-Pyrroline-. 5- ...
Aspartate--ammonia ligase (EC 6.3.1.1). asnS Oenococcus oeni PSU-1 Gene: OEOE_1097: Asparaginyl-tRNA synthetase (EC 6.1.1.22) ... Gene: LBUL_1111: Asparaginyl-tRNA synthetase (EC 6.1.1.22). Gene: LBUL_0911: Asparaginyl-tRNA synthetase (EC 6.1.1.22) ... Gene: lp_0956: Asparaginyl-tRNA synthetase (EC 6.1.1.22). Gene: lp_1740: Asparaginyl-tRNA synthetase (EC 6.1.1.22) ...
Aspartate 1-decarboxylase (NCBI ptt file). 329, 450. BC1672. BC1672. Metal-dependent hydrolase related to alanyl-tRNA ... Pantoate--beta-alanine ligase (NCBI ptt file). 329, 450. BC1542. BC1542. ...
glutamate-tRNA ligase activity GO:0004818 * lysosomal proton-transporting V-type ATPase complex ... cis-14-hydroxy-10,13-dioxo-7-heptadecenoic acid peptidyl-aspartate ester biosynthetic process from peptidyl-aspartic acid ...
glutamate-ammonia ligase. IDA. ISO. SMPDB. RGD. PMID:4403443 PMID:28323. SMP:00072, RGD:2301548, RGD:2301547. NCBI chr13: ... glutamyl-tRNA synthetase 2, mitochondrial. ISO. SMPDB. SMP:00072. NCBI chr 1:176,597,986...176,625,848 Ensembl chr 1: ... carbamoyl-phosphate synthetase 2, aspartate transcarbamylase, and dihydroorotase. ISO. SMPDB. SMP:00072. NCBI chr 6:25,292,133 ... glutamate-cysteine ligase, catalytic subunit. ISO. SMPDB. SMP:00072. NCBI chr 8:78,629,899...78,668,547 Ensembl chr 8: ...
6. Single bond formation by eliminating the elements of water. Hydrolases break bonds by adding the elements of water; ligases ... tRNA synthetase is illustrated in this figure:. ... amino group between alanine and aspartate: Other transferases ... Synthetases are a subclass of ligases that use the hydrolysis of ATP to drive this formation. For example, aminoacyl‐transfer ...
Genetic information processing Protein synthesis tRNA and rRNA base modification tRNA:m(5)U-54 methyltransferase (TIGR00137; EC ... Metabolism Biosynthesis of cofactors, prosthetic groups, and carriers Pyridine nucleotides L-aspartate oxidase (TIGR00551; EC ... D-glutamate ligase (TIGR01087; EC 6.3.2.9; HMM-score: 11.3) ... Genetic information processing Protein synthesis tRNA and rRNA ... base modification tRNA U-34 5-methylaminomethyl-2-thiouridine biosynthesis protein MnmC, C-terminal domain (TIGR03197; HMM- ...
Glutamate----tRNA ligase (GltX). P99170. 1.74 ↓. 1.72 ↓. 2. 1-pyrroline-5-carboxylate dehydrogenase (RocA). P99076. 1.96 ↓. ... Serine-aspartate repeat-containing protein D (SdrD). Q7A780. 1.58 ↑. * the arrow denotes the direction of regulation; ↑ up- and ... Succinate--CoA ligase (ADP-forming) subunit α (SucD). P99070. 1.55 ↓. 3. Putative peptidyl-prolyl cis-trans isomerase (PpiB). ... Formate--tetrahydrofolate ligase (FHS). Q7A535. 3.41 ↓. 2.75 ↓. 18. Phosphoenolpyruvate-protein phosphotransferase (PtsI). ...
  • Other names in common use include aspartyl-tRNA synthetase, aspartyl ribonucleic synthetase, aspartyl-transfer RNA synthetase, aspartic acid translase, aspartyl-transfer ribonucleic acid synthetase, and aspartyl ribonucleate synthetase. (wikipedia.org)
  • Studies on aspartyl-tRNA synthetase from Baker's yeast. (wikipedia.org)
  • The DARS2 gene provides instructions for making an enzyme called mitochondrial aspartyl-tRNA synthetase. (medlineplus.gov)
  • Enzymes called aminoacyl-tRNA synthetases, including mitochondrial aspartyl-tRNA synthetase, attach a particular amino acid to a specific tRNA. (medlineplus.gov)
  • Mitochondrial aspartyl-tRNA synthetase attaches the amino acid aspartic acid to the correct tRNA, which helps ensure that aspartic acid is added at the proper place in the mitochondrial protein. (medlineplus.gov)
  • The most common mutation that causes this condition disrupts the way genetic information is pieced together to make a blueprint for producing the mitochondrial aspartyl-tRNA synthetase enzyme. (medlineplus.gov)
  • This type of mutation results in decreased mitochondrial aspartyl-tRNA synthetase enzyme activity. (medlineplus.gov)
  • Researchers do not understand why reduced activity of mitochondrial aspartyl-tRNA synthetase specifically affects certain parts of the brain and spinal cord. (medlineplus.gov)
  • Biochemical and structural characterization of mycobacterial aspartyl-tRNA synthetase AspS, a promising TB drug target. (aston.ac.uk)
  • With reduced activity, the enzyme has difficulty adding aspartic acid to the tRNA, which hinders the addition of this amino acid to mitochondrial proteins. (medlineplus.gov)
  • This enzyme participates in alanine and aspartate metabolism and aminoacyl-trna biosynthesis. (wikipedia.org)
  • tRNA synthetase class II core domain (G, Seryl-tRNA synthetase N-terminal domain [Interproscan]. (ntu.edu.sg)
  • During protein synthesis, in either the mitochondria or the cytoplasm, a type of RNA called transfer RNA (tRNA) helps assemble protein building blocks (amino acids) into a chain that forms the protein. (medlineplus.gov)
  • Glutamate-cysteine ligase family 2(GCS2) [Interproscan]. (ntu.edu.sg)
  • Each tRNA carries a specific amino acid to the growing chain. (medlineplus.gov)
  • In enzymology, an aspartate-tRNA ligase (EC 6.1.1.12) is an enzyme that catalyzes the chemical reaction ATP + L-aspartate + tRNAAsp ⇌ {\displaystyle \rightleftharpoons } AMP + diphosphate + L-aspartyl-tRNAAsp The 3 substrates of this enzyme are ATP, L-aspartate, and tRNA(Asp), whereas its 3 products are AMP, diphosphate, and L-aspartyl-tRNA(Asp). (wikipedia.org)
  • This enzyme belongs to the family of ligases, to be specific those forming carbon-oxygen bonds in aminoacyl-tRNA and related compounds. (wikipedia.org)
  • The systematic name of this enzyme class is L-aspartate:tRNAAsp ligase (AMP-forming). (wikipedia.org)
  • To analyse the impact of inhibitor 1 on M. tuberculosis AspS (Mt-AspS) activity we over-expressed, purified and characterised the kinetics of this enzyme using a robust tRNA-independent assay adapted to a high-throughput screening format. (aston.ac.uk)
  • Pantoate-beta-alanine ligase [Interproscan]. (ntu.edu.sg)
  • D-ala D-ala ligase C-terminus, D-ala D-ala ligase N-terminus [Interproscan]. (ntu.edu.sg)
  • In addition, tRNA modification by the Geobacillus kaustophilus specific tRNA methyltransferases probably aids in the thermoadaptation of this organism. (up.ac.za)
  • ligases carry out the converse reaction, removing the elements of water from two functional groups to form a single bond. (cliffsnotes.com)
  • Other names in common use include aspartyl-tRNA synthetase, aspartyl ribonucleic synthetase, aspartyl-transfer RNA synthetase, aspartic acid translase, aspartyl-transfer ribonucleic acid synthetase, and aspartyl ribonucleate synthetase. (wikipedia.org)
  • Studies on aspartyl-tRNA synthetase from Baker's yeast. (wikipedia.org)
  • The DARS2 gene provides instructions for making an enzyme called mitochondrial aspartyl-tRNA synthetase. (medlineplus.gov)
  • Enzymes called aminoacyl-tRNA synthetases, including mitochondrial aspartyl-tRNA synthetase, attach a particular amino acid to a specific tRNA. (medlineplus.gov)
  • Mitochondrial aspartyl-tRNA synthetase attaches the amino acid aspartic acid to the correct tRNA, which helps ensure that aspartic acid is added at the proper place in the mitochondrial protein. (medlineplus.gov)
  • The most common mutation that causes this condition disrupts the way genetic information is pieced together to make a blueprint for producing the mitochondrial aspartyl-tRNA synthetase enzyme. (medlineplus.gov)
  • This type of mutation results in decreased mitochondrial aspartyl-tRNA synthetase enzyme activity. (medlineplus.gov)
  • Researchers do not understand why reduced activity of mitochondrial aspartyl-tRNA synthetase specifically affects certain parts of the brain and spinal cord. (medlineplus.gov)
  • The protein encoded by this gene belongs to the class-II aminoacyl-tRNA synthetase family. (nih.gov)
  • Histidyl-tRNA synthetase and asparaginyl-tRNA synthetase, autoantigens in myositis, activate chemokine receptors on T lymphocytes and immature dendritic cells. (mcw.edu)
  • Autoantibodies to histidyl-tRNA synthetase (HisRS) or to alanyl-, asparaginyl-, glycyl-, isoleucyl-, or threonyl-tRNA synthetase occur in approximately 25% of patients with polymyositis or dermatomyositis. (mcw.edu)
  • Asparaginyl-tRNA synthetase induced migration of lymphocytes, activated monocytes, iDCs, and CCR3-transfected HEK-293 cells. (mcw.edu)
  • Seryl-tRNA synthetase induced migration of CCR3-transfected cells but not iDCs. (mcw.edu)
  • acetylated processed McC no longer inhibits aspartyl-tRNA synthetase. (medscape.com)
  • [ 31 ] Acetylation of the α-amino group of the amino acid adenylate would both disrupt favorable hydrogen bond interactions and result in steric clashes with the backbone of aspartyl-tRNA synthetase, which provides structural rationale for MccE CTD protective function. (medscape.com)
  • However, it is noteworthy that agrocin 84 is a Trojan horse inhibitor of leucyl-tRNA synthetase, whose active part is a nonhydrolyzable leucyl adenylate with a phosporamide bond in the same position as in McC. (medscape.com)
  • Leucyl-tRNA synthetase, tRNA synthetases class I (I, Anticodon-binding domain of tRNA [Interproscan]. (ntu.edu.sg)
  • This enzyme belongs to the family of ligases, to be specific those forming carbon-oxygen bonds in aminoacyl-tRNA and related compounds. (wikipedia.org)
  • This enzyme participates in alanine and aspartate metabolism and aminoacyl-trna biosynthesis. (wikipedia.org)
  • We tested the ability of several aminoacyl-tRNA synthetases to induce leukocyte migration. (mcw.edu)
  • Thus, autoantigenic aminoacyl-tRNA synthetases, perhaps liberated from damaged muscle cells, may perpetuate the development of myositis by recruiting mononuclear cells that induce innate and adaptive immune responses. (mcw.edu)
  • In enzymology, an aspartate-tRNA ligase (EC 6.1.1.12) is an enzyme that catalyzes the chemical reaction ATP + L-aspartate + tRNAAsp ⇌ {\displaystyle \rightleftharpoons } AMP + diphosphate + L-aspartyl-tRNAAsp The 3 substrates of this enzyme are ATP, L-aspartate, and tRNA(Asp), whereas its 3 products are AMP, diphosphate, and L-aspartyl-tRNA(Asp). (wikipedia.org)
  • peptidyl-tRNA hydrolase, ribosome-attached [Ensembl]. (ntu.edu.sg)
  • The E.coli ribosome has how many binding sites for tRNA? (flashcardmachine.com)
  • L-phenylalanine is a competitive antagonist for the glycine- and glutamate-binding sites of N-methyl-D-aspartate receptors (NMDARs) ( K B of 573 μM ) and non-NMDARs , respectively. (medchemexpress.com)
  • 18927 aspartate-semialdehyde dehydrogenase asd BBZA01000003 CDS ARMA_0047 18924. (go.jp)
  • Link to all annotated objects annotated to ligase activity, forming carbon-nitrogen bonds. (planteome.org)
  • Link to all direct and indirect annotations to ligase activity, forming carbon-nitrogen bonds. (planteome.org)
  • 12558 2-aminobenzoate-CoA ligase abmG BBZA01000002 CDS ARMA_0024 12542. (go.jp)
  • The PTEN download Windows for HSF1( HSE, aspartate symbol uridine) covers transfer of new transcripts acid in well-being SUMOylation, with at least three Laminins representing annealed for the transcriptional phosphate acetyl. (evakoch.com)