Selenocysteine
A naturally occurring amino acid in both eukaryotic and prokaryotic organisms. It is found in tRNAs and in the catalytic site of some enzymes. The genes for glutathione peroxidase and formate dehydrogenase contain the TGA codon, which codes for this amino acid.
Selenoproteins
Selenoproteins are proteins that specifically incorporate SELENOCYSTEINE into their amino acid chain. Most selenoproteins are enzymes with the selenocysteine residues being responsible for their catalytic functions.
RNA, Transfer, Amino Acid-Specific
Selenium
An element with the atomic symbol Se, atomic number 34, and atomic weight 78.96. It is an essential micronutrient for mammals and other animals but is toxic in large amounts. Selenium protects intracellular structures against oxidative damage. It is an essential component of GLUTATHIONE PEROXIDASE.
Selenoprotein P
An extracellular selenoprotein that contains most of the SELENIUM in PLASMA. Selenoprotein P functions as an antioxidant and appears to transport selenium from the LIVER to peripheral tissues.
Thioredoxin-Disulfide Reductase
Formate Dehydrogenases
Flavoproteins that catalyze reversibly the reduction of carbon dioxide to formate. Many compounds can act as acceptors, but the only physiologically active acceptor is NAD. The enzymes are active in the fermentation of sugars and other compounds to carbon dioxide and are the key enzymes in obtaining energy when bacteria are grown on formate as the main carbon source. They have been purified from bovine blood. EC 1.2.1.2.
Codon, Terminator
Selenium Radioisotopes
RNA, Transfer, Ser
Glutathione Peroxidase
Selenoprotein W
RNA, Transfer, Amino Acyl
Intermediates in protein biosynthesis. The compounds are formed from amino acids, ATP and transfer RNA, a reaction catalyzed by aminoacyl tRNA synthetase. They are key compounds in the genetic translation process.
Organoselenium Compounds
Organic compounds which contain selenium as an integral part of the molecule.
Codon
A set of three nucleotides in a protein coding sequence that specifies individual amino acids or a termination signal (CODON, TERMINATOR). Most codons are universal, but some organisms do not produce the transfer RNAs (RNA, TRANSFER) complementary to all codons. These codons are referred to as unassigned codons (CODONS, NONSENSE).
Lyases
Sodium Selenite
The disodium salt of selenious acid. It is used therapeutically to supply the trace element selenium and is prepared by the reaction of SELENIUM DIOXIDE with SODIUM HYDROXIDE.
Molecular Sequence Data
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Selenious Acid
Iodide Peroxidase
A hemeprotein that catalyzes the oxidation of the iodide radical to iodine with the subsequent iodination of many organic compounds, particularly proteins. EC 1.11.1.8.
Nucleic Acid Conformation
Base Sequence
Selenium Compounds
Inorganic compounds that contain selenium as an integral part of the molecule.
Peptide Elongation Factors
3' Untranslated Regions
Methionine Sulfoxide Reductases
Protein Biosynthesis
The biosynthesis of PEPTIDES and PROTEINS on RIBOSOMES, directed by MESSENGER RNA, via TRANSFER RNA that is charged with standard proteinogenic AMINO ACIDS.
Hydrogenase
Amino Acid Sequence
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
Amebicides
Proteins
Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.
Methanococcales
Anticodon
The sequential set of three nucleotides in TRANSFER RNA that interacts with its complement in MESSENGER RNA, the CODON, during translation in the ribosome.
Selenium-Binding Proteins
Escherichia coli
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
Methanococcus
Transferases
Transferases are enzymes transferring a group, for example, the methyl group or a glycosyl group, from one compound (generally regarded as donor) to another compound (generally regarded as acceptor). The classification is based on the scheme "donor:acceptor group transferase". (Enzyme Nomenclature, 1992) EC 2.
RNA-Binding Proteins
Proteins that bind to RNA molecules. Included here are RIBONUCLEOPROTEINS and other proteins whose function is to bind specifically to RNA.
Carbon-Sulfur Lyases
RNA, Messenger
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
Sulfur
An element that is a member of the chalcogen family. It has an atomic symbol S, atomic number 16, and atomic weight [32.059; 32.076]. It is found in the amino acids cysteine and methionine.
Cloning, Molecular
Sequence Homology, Amino Acid
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
Catalysis
Biocatalysis
Auranofin
An oral chrysotherapeutic agent for the treatment of rheumatoid arthritis. Its exact mechanism of action is unknown, but it is believed to act via immunological mechanisms and alteration of lysosomal enzyme activity. Its efficacy is slightly less than that of injected gold salts, but it is better tolerated, and side effects which occur are potentially less serious.
Sequence Alignment
The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.