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Acyl Carrier Protein: Consists of a polypeptide chain and 4'-phosphopantetheine linked to a serine residue by a phosphodiester bond. Acyl groups are bound as thiol esters to the pantothenyl group. Acyl carrier protein is involved in every step of fatty acid synthesis by the cytoplasmic system.Acyl-Carrier Protein S-Malonyltransferase: This enzyme catalyzes the transacylation of malonate from MALONYL CoA to activated holo-ACP, to generate malonyl-(acyl-carrier protein), which is an elongation substrate in FATTY ACIDS biosynthesis. It is an essential enzyme in the biosynthesis of FATTY ACIDS in all BACTERIA.Malonyl Coenzyme A: A coenzyme A derivative which plays a key role in the fatty acid synthesis in the cytoplasmic and microsomal systems.Acyltransferases: Enzymes from the transferase class that catalyze the transfer of acyl groups from donor to acceptor, forming either esters or amides. (From Enzyme Nomenclature 1992) EC 2.3.Protein S: The vitamin K-dependent cofactor of activated PROTEIN C. Together with protein C, it inhibits the action of factors VIIIa and Va. A deficiency in protein S; (PROTEIN S DEFICIENCY); can lead to recurrent venous and arterial thrombosis.Pantetheine: An intermediate in the pathway of coenzyme A formation in mammalian liver and some microorganisms.Fatty Acid Synthase, Type II: The form of fatty acid synthase complex found in BACTERIA; FUNGI; and PLANTS. Catalytic steps are like the animal form but the protein structure is different with dissociated enzymes encoded by separate genes. It is a target of some ANTI-INFECTIVE AGENTS which result in disruption of the CELL MEMBRANE and CELL WALL.3-Oxoacyl-(Acyl-Carrier-Protein) Synthase: An enzyme of long-chain fatty acid synthesis, that adds a two-carbon unit from malonyl-(acyl carrier protein) to another molecule of fatty acyl-(acyl carrier protein), giving a beta-ketoacyl-(acyl carrier protein) with the release of carbon dioxide. EC 2.3.1.41.Polyketide Synthases: Large enzyme complexes composed of a number of component enzymes that are found in STREPTOMYCES which biosynthesize MACROLIDES and other polyketides.Fatty Acid Synthases: Enzymes that catalyze the synthesis of FATTY ACIDS from acetyl-CoA and malonyl-CoA derivatives.Transferases (Other Substituted Phosphate Groups): A class of enzymes that transfers substituted phosphate groups. EC 2.7.8.3-Oxoacyl-(Acyl-Carrier-Protein) Reductase: A 3-oxoacyl reductase that has specificity for ACYL CARRIER PROTEIN-derived FATTY ACIDS.Coenzyme APantothenic Acid: A butyryl-beta-alanine that can also be viewed as pantoic acid complexed with BETA ALANINE. It is incorporated into COENZYME A and protects cells against peroxidative damage by increasing the level of GLUTATHIONE.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.Protein S Deficiency: An autosomal dominant disorder showing decreased levels of plasma protein S antigen or activity, associated with venous thrombosis and pulmonary embolism. PROTEIN S is a vitamin K-dependent plasma protein that inhibits blood clotting by serving as a cofactor for activated PROTEIN C (also a vitamin K-dependent protein), and the clinical manifestations of its deficiency are virtually identical to those of protein C deficiency. Treatment with heparin for acute thrombotic processes is usually followed by maintenance administration of coumarin drugs for the prevention of recurrent thrombosis. (From Harrison's Principles of Internal Medicine, 12th ed, p1511; Wintrobe's Clinical Hematology, 9th ed, p1523)Carrier Proteins: Transport proteins that carry specific substances in the blood or across cell membranes.Enoyl-(Acyl-Carrier-Protein) Reductase (NADH): An NAD-dependent enzyme that catalyzes the oxidation of acyl-[acyl-carrier protein] to trans-2,3-dehydroacyl-[acyl-carrier protein]. It has a preference for acyl groups with a carbon chain length between 4 to 16.Carbon-Sulfur Ligases: Enzymes that catalyze the joining of two molecules by the formation of a carbon-sulfur bond. EC 6.2.Ribosomal Protein S6: A ribosomal protein that may play a role in controlling cell growth and proliferation. It is a major substrate of RIBOSOMAL PROTEIN S6 KINASES and plays a role in regulating the translation (TRANSLATION, GENETIC) of RNAs that contain an RNA 5' TERMINAL OLIGOPYRIMIDINE SEQUENCE.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.Fatty Acids: Organic, monobasic acids derived from hydrocarbons by the equivalent of oxidation of a methyl group to an alcohol, aldehyde, and then acid. Fatty acids are saturated and unsaturated (FATTY ACIDS, UNSATURATED). (Grant & Hackh's Chemical Dictionary, 5th ed)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.Acylation: The addition of an organic acid radical into a molecule.Thiolester HydrolasesTriclosan: A diphenyl ether derivative used in cosmetics and toilet soaps as an antiseptic. It has some bacteriostatic and fungistatic action.Bacterial Proteins: Proteins found in any species of bacterium.Streptomyces: A genus of bacteria that form a nonfragmented aerial mycelium. Many species have been identified with some being pathogenic. This genus is responsible for producing a majority of the ANTI-BACTERIAL AGENTS of practical value.Ribosomal Proteins: Proteins found in ribosomes. They are believed to have a catalytic function in reconstituting biologically active ribosomal subunits.Cerulenin: An epoxydodecadienamide isolated from several species, including ACREMONIUM, Acrocylindrum, and Helicoceras. It inhibits the biosynthesis of several lipids by interfering with enzyme function.Saccharopolyspora: A genus of gram-positive bacteria whose spores are round to oval and covered by a sheath.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.Apoproteins: The protein components of a number of complexes, such as enzymes (APOENZYMES), ferritin (APOFERRITINS), or lipoproteins (APOLIPOPROTEINS).Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Substrate Specificity: A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.Acyl Coenzyme A: S-Acyl coenzyme A. Fatty acid coenzyme A derivatives that are involved in the biosynthesis and oxidation of fatty acids as well as in ceramide formation.Cloning, Molecular: The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.Anthraquinones: Compounds based on ANTHRACENES which contain two KETONES in any position. Substitutions can be in any position except on the ketone groups.Coriandrum: A plant genus of the family APIACEAE. The leaves are the source of cilantro and the seeds are the source of coriander, both of which are used in SPICES.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Multienzyme Complexes: Systems of enzymes which function sequentially by catalyzing consecutive reactions linked by common metabolic intermediates. They may involve simply a transfer of water molecules or hydrogen atoms and may be associated with large supramolecular structures such as MITOCHONDRIA or RIBOSOMES.Acyl-Carrier Protein S-Acetyltransferase: A enzyme that catalyzes the transfer of acetyl groups from ACETYL CoA to acyl-carrier protein to form COENZYME A and acetyl-acyl-carrier protein.MalonatesProtein Conformation: The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).Kinetics: The rate dynamics in chemical or physical systems.Thioctic Acid: An octanoic acid bridged with two sulfurs so that it is sometimes also called a pentanoic acid in some naming schemes. It is biosynthesized by cleavage of LINOLEIC ACID and is a coenzyme of oxoglutarate dehydrogenase (KETOGLUTARATE DEHYDROGENASE COMPLEX). It is used in DIETARY SUPPLEMENTS.Lipid A: Lipid A is the biologically active component of lipopolysaccharides. It shows strong endotoxic activity and exhibits immunogenic properties.Naphthacenes: Polyacenes with four ortho-fused benzene rings in a straight linear arrangement. This group is best known for the subclass called TETRACYCLINES.Crystallography, X-Ray: The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Peptide Synthases: Ligases that catalyze the joining of adjacent AMINO ACIDS by the formation of carbon-nitrogen bonds between their carboxylic acid groups and amine groups.Protein Structure, Tertiary: The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.Recombinant Proteins: Proteins prepared by recombinant DNA technology.Acetyl Coenzyme A: Acetyl CoA participates in the biosynthesis of fatty acids and sterols, in the oxidation of fatty acids and in the metabolism of many amino acids. It also acts as a biological acetylating agent.Plants: Multicellular, eukaryotic life forms of kingdom Plantae (sensu lato), comprising the VIRIDIPLANTAE; RHODOPHYTA; and GLAUCOPHYTA; all of which acquired chloroplasts by direct endosymbiosis of CYANOBACTERIA. They are characterized by a mainly photosynthetic mode of nutrition; essentially unlimited growth at localized regions of cell divisions (MERISTEMS); cellulose within cells providing rigidity; the absence of organs of locomotion; absence of nervous and sensory systems; and an alternation of haploid and diploid generations.Escherichia coli Proteins: Proteins obtained from ESCHERICHIA COLI.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Ligases: 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.Protein Binding: The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Protein C: A vitamin-K dependent zymogen present in the blood, which, upon activation by thrombin and thrombomodulin exerts anticoagulant properties by inactivating factors Va and VIIIa at the rate-limiting steps of thrombin formation.Multigene Family: A set of genes descended by duplication and variation from some ancestral gene. Such genes may be clustered together on the same chromosome or dispersed on different chromosomes. Examples of multigene families include those that encode the hemoglobins, immunoglobulins, histocompatibility antigens, actins, tubulins, keratins, collagens, heat shock proteins, salivary glue proteins, chorion proteins, cuticle proteins, yolk proteins, and phaseolins, as well as histones, ribosomal RNA, and transfer RNA genes. The latter three are examples of reiterated genes, where hundreds of identical genes are present in a tandem array. (King & Stanfield, A Dictionary of Genetics, 4th ed)Genetic Complementation Test: A test used to determine whether or not complementation (compensation in the form of dominance) will occur in a cell with a given mutant phenotype when another mutant genome, encoding the same mutant phenotype, is introduced into that cell.Vibrio: A genus of VIBRIONACEAE, made up of short, slightly curved, motile, gram-negative rods. Various species produce cholera and other gastrointestinal disorders as well as abortion in sheep and cattle.Genes, Bacterial: The functional hereditary units of BACTERIA.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.Carrier State: The condition of harboring an infective organism without manifesting symptoms of infection. The organism must be readily transmissible to another susceptible host.Nuclear Magnetic Resonance, Biomolecular: NMR spectroscopy on small- to medium-size biological macromolecules. This is often used for structural investigation of proteins and nucleic acids, and often involves more than one isotope.Macrolides: A group of often glycosylated macrocyclic compounds formed by chain extension of multiple PROPIONATES cyclized into a large (typically 12, 14, or 16)-membered lactone. Macrolides belong to the POLYKETIDES class of natural products, and many members exhibit ANTIBIOTIC properties.Mycolic AcidsSulfhydryl Compounds: Compounds containing the -SH radical.Complement Inactivator Proteins: Serum proteins that negatively regulate the cascade process of COMPLEMENT ACTIVATION. Uncontrolled complement activation and resulting cell lysis is potentially dangerous for the host. The complement system is tightly regulated by inactivators that accelerate the decay of intermediates and certain cell surface receptors.Polyketides: Natural compounds containing alternating carbonyl and methylene groups (beta-polyketones), bioenergenetically derived from repeated condensation of acetyl coenzyme A via malonyl coenzyme A, in a process similar to fatty acid synthesis.Biocatalysis: The facilitation of biochemical reactions with the aid of naturally occurring catalysts such as ENZYMES.Magnetic Resonance Spectroscopy: Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).Protein Structure, Secondary: The level of protein structure in which regular hydrogen-bond interactions within contiguous stretches of polypeptide chain give rise to alpha helices, beta strands (which align to form beta sheets) or other types of coils. This is the first folding level of protein conformation.Glycerol-3-Phosphate O-Acyltransferase: An enzyme that transfers acyl groups from acyl-CoA to glycerol-3-phosphate to form monoglyceride phosphates. It acts only with CoA derivatives of fatty acids of chain length above C-10. Also forms diglyceride phosphates. EC 2.3.1.15.Alcohol Oxidoreductases: A subclass of enzymes which includes all dehydrogenases acting on primary and secondary alcohols as well as hemiacetals. They are further classified according to the acceptor which can be NAD+ or NADP+ (subclass 1.1.1), cytochrome (1.1.2), oxygen (1.1.3), quinone (1.1.5), or another acceptor (1.1.99).Molecular Structure: The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.Ribosomal Protein S6 Kinases: A family of protein serine/threonine kinases which act as intracellular signalling intermediates. Ribosomal protein S6 kinases are activated through phosphorylation in response to a variety of HORMONES and INTERCELLULAR SIGNALING PEPTIDES AND PROTEINS. Phosphorylation of RIBOSOMAL PROTEIN S6 by enzymes in this class results in increased expression of 5' top MRNAs. Although specific for RIBOSOMAL PROTEIN S6 members of this class of kinases can act on a number of substrates within the cell. The immunosuppressant SIROLIMUS inhibits the activation of ribosomal protein S6 kinases.Brassica: A plant genus of the family Cruciferae. It contains many species and cultivars used as food including cabbage, cauliflower, broccoli, Brussel sprouts, kale, collard greens, MUSTARD PLANT; (B. alba, B. junica, and B. nigra), turnips (BRASSICA NAPUS) and rapeseed (BRASSICA RAPA).Hydro-Lyases: Enzymes that catalyze the breakage of a carbon-oxygen bond leading to unsaturated products via the removal of water. EC 4.2.1.