Lactones: Cyclic esters of hydroxy carboxylic acids, containing a 1-oxacycloalkan-2-one structure. Large cyclic lactones of over a dozen atoms are MACROLIDES.4-Butyrolactone: One of the FURANS with a carbonyl thereby forming a cyclic lactone. It is an endogenous compound made from gamma-aminobutyrate and is the precursor of gamma-hydroxybutyrate. It is also used as a pharmacological agent and solvent.Acyl-Butyrolactones: Cyclic esters of acylated BUTYRIC ACID containing four carbons in the ring.Quorum Sensing: A phenomenon where microorganisms communicate and coordinate their behavior by the accumulation of signaling molecules. A reaction occurs when a substance accumulates to a sufficient concentration. This is most commonly seen in bacteria.HomoserineSesquiterpenesPyrones: Keto-pyrans.Chromobacterium: A genus of gram-negative, facultatively anaerobic, rod-shaped bacteria occurring in soil and water. Its organisms are generally nonpathogenic, but some species do cause infections of mammals, including humans.Sesquiterpenes, Germacrane: SESQUITERPENES cyclized to one 10-carbon ring.Pectobacterium carotovorum: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria that causes rotting, particularly of storage tissues, of a wide variety of plants and causes a vascular disease in CARROTS; and POTATO plants.Gene Expression Regulation, Bacterial: Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.Group VI Phospholipases A2: A calcium-independent phospholipase A2 group that may play a role in membrane phospholipid remodeling and homeostasis by controling the levels of PHOSPHATIDYLCHOLINE in mammalian cell membranes.Pseudomonas aeruginosa: A species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. aeruginosa is a major agent of nosocomial infection.Asteraceae: A large plant family of the order Asterales, subclass Asteridae, class Magnoliopsida. The family is also known as Compositae. Flower petals are joined near the base and stamens alternate with the corolla lobes. The common name of "daisy" refers to several genera of this family including Aster; CHRYSANTHEMUM; RUDBECKIA; TANACETUM.Vernonia: A plant genus of the family ASTERACEAE. Members contain germacrane and sesquiterpene LACTONES.Saussurea: A plant genus of the family ASTERACEAE, order Asterales, subclass Asteridae. It is a source of costus root oil and should not be confused with the genus COSTUS.Bacterial Proteins: Proteins found in any species of bacterium.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.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.Furans: Compounds with a 5-membered ring of four carbons and an oxygen. They are aromatic heterocycles. The reduced form is tetrahydrofuran.Zearalenone: (S-(E))-3,4,5,6,8,10-Hexahydro-14,16-dihydroxy-3-methyl-1H-2-benzoxacyclotetradecin-1,7(8H)-dione. One of a group of compounds known under the general designation of resorcylic acid lactones. Cis, trans, dextro and levo forms have been isolated from the fungus Gibberella zeae (formerly Fusarium graminearum). They have estrogenic activity, cause toxicity in livestock as feed contaminant, and have been used as anabolic or estrogen substitutes.Sesquiterpenes, Guaiane: SESQUITERPENES cyclized into two adjoining rings, one being 7-carbons and the other is 5-carbons.Agrobacterium tumefaciens: A species of gram-negative, aerobic bacteria isolated from soil and the stems, leafs, and roots of plants. Some biotypes are pathogenic and cause the formation of PLANT TUMORS in a wide variety of higher plants. The species is a major research tool in biotechnology.Carboxylic Ester Hydrolases: Enzymes which catalyze the hydrolysis of carboxylic acid esters with the formation of an alcohol and a carboxylic acid anion.Sugar AcidsTanacetum parthenium: An aromatic perennial plant species that has been used to treat migraines, arthritis, and as a febrifuge. It contains TANNINS, volatile oils (OILS, ESSENTIAL), and sesquiterpene lactones, especially parthenolide.Aliivibrio fischeri: A species of gram-negative bacteria in the genus ALIIVIBRIO, which exhibits LUMINESCENCE. A. fischeri is found in a symbiotic relationship with the SQUID Euprymna scolopes.Sesquiterpenes, Eudesmane: SESQUITERPENES cyclized into two adjoining cyclohexane rings but with a different configuration from the ARTEMISININS.Laurus: A plant genus in the LAURACEAE family. Laurus nobilis L. leaves are known for use in SPICES, having a similar flavor as UMBELLULARIA.Naphthalenes: Two-ring crystalline hydrocarbons isolated from coal tar. They are used as intermediates in chemical synthesis, as insect repellents, fungicides, lubricants, preservatives, and, formerly, as topical antiseptics.Chicory: A thick-rooted perennial (Cichorium intybus) native to Europe but widely grown for its young leaves used as salad greens and for its roots, dried and ground-roasted, used to flavor or adulterate coffee. (From Webster, 3d ed)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.Serratia: A genus of gram-negative, facultatively anaerobic, rod-shaped bacteria that occurs in the natural environment (soil, water, and plant surfaces) or as an opportunistic human pathogen.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).Burkholderia: A genus of gram-negative, aerobic, rod-shaped bacteria. Organisms in this genus had originally been classified as members of the PSEUDOMONAS genus but overwhelming biochemical and chemical findings indicated the need to separate them from other Pseudomonas species, and hence, this new genus was created.Pyocyanine: Antibiotic pigment produced by Pseudomonas aeruginosa.Plant Extracts: Concentrated pharmaceutical preparations of plants obtained by removing active constituents with a suitable solvent, which is evaporated away, and adjusting the residue to a prescribed standard.Bryostatins: A group of 20-member macrolactones in which there are three remotely substituted pyran rings that are linked by a methylene bridge and an E-disubstituted alkene, and have geminal dimethyls at C8 and C18 carbons. Some interact with PROTEIN KINASE C.Chromatography, Thin Layer: Chromatography on thin layers of adsorbents rather than in columns. The adsorbent can be alumina, silica gel, silicates, charcoals, or cellulose. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Camptothecin: An alkaloid isolated from the stem wood of the Chinese tree, Camptotheca acuminata. This compound selectively inhibits the nuclear enzyme DNA TOPOISOMERASES, TYPE I. Several semisynthetic analogs of camptothecin have demonstrated antitumor activity.Pantoea: A genus of gram-negative, facultatively anaerobic, straight rods which are motile by peritrichous flagella. Most strains produce a yellow pigment. This organism is isolated from plant surfaces, seeds, soil, and water, as well as from animals and human wounds, blood, and urine. (From Bergey's Manual of Determinative Bacteriology, 9th ed)Chromatography, High Pressure Liquid: Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.Phosphoric Triester Hydrolases: A class of enzymes that catalyze the hydrolysis of one of the three ester bonds in a phosphotriester-containing compound.Ginkgo biloba: The only specie of the genus Ginkgo, family Ginkgoacea. It is the source of extracts of medicinal interest, especially Egb 761. Ginkgo may refer to the genus or species.Withanolides: Ergostane derivatives of 28 carbons with oxygens at C1, C22, and C26 positions and the side chain cyclized. They are found in WITHANIA plant genus and have cytotoxic and other effects.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.Phospholipases A2: Phospholipases that hydrolyze the acyl group attached to the 2-position of PHOSPHOGLYCERIDES.Terpenes: A class of compounds composed of repeating 5-carbon units of HEMITERPENES.Stereoisomerism: The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)Inula: A plant genus of the family ASTERACEAE. Members contain INULIN, alantol, helenin, alantic acid, and acrid resin.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.Biofilms: Encrustations, formed from microbes (bacteria, algae, fungi, plankton, or protozoa) embedding in extracellular polymers, that adhere to surfaces such as teeth (DENTAL DEPOSITS); PROSTHESES AND IMPLANTS; and catheters. Biofilms are prevented from forming by treating surfaces with DENTIFRICES; DISINFECTANTS; ANTI-INFECTIVE AGENTS; and antifouling agents.Phospholipases A: Phospholipases that hydrolyze one of the acyl groups of phosphoglycerides or glycerophosphatidates.Topotecan: An antineoplastic agent used to treat ovarian cancer. It works by inhibiting DNA TOPOISOMERASES, TYPE I.Phospholipases A2, Calcium-Independent: A subcategory of structurally-related phospholipases A2 that do not require calcium for activity.Andrographis: A plant genus of the family ACANTHACEAE. Members contain andrographolide and other DITERPENES and androechin, a CHALCONE.Chrysanthemum cinerariifolium: A plant species of the genus CHRYSANTHEMUM, family ASTERACEAE. The flowers contain PYRETHRINS, cinerolones, and chrysanthemines which are powerful contact insecticides. Most in the old Pyrethrum genus are reclassified to TANACETUM; some to other ASTERACEAE genera.Trans-Activators: Diffusible gene products that act on homologous or heterologous molecules of viral or cellular DNA to regulate the expression of proteins.Carboxylic Acids: Organic compounds containing the carboxy group (-COOH). This group of compounds includes amino acids and fatty acids. Carboxylic acids can be saturated, unsaturated, or aromatic.Antineoplastic Agents, Phytogenic: Agents obtained from higher plants that have demonstrable cytostatic or antineoplastic activity.Mass Spectrometry: An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.Artemisia annua: A plant species of the genus ARTEMISIA, family ASTERACEAE. It is the source of the antimalarial artemisinin (ANTIMALARIALS).Santonin: Anthelmintic isolated from the dried unexpanded flower heads of Artemisia maritima and other species of Artemisia found principally in Russian and Chinese Turkestan and the Southern Ural region. (From Merck, 11th ed.)Plant Components, Aerial: The above-ground plant without the roots.GluconatesHydrogen Cyanide: Hydrogen cyanide (HCN); A toxic liquid or colorless gas. It is found in the smoke of various tobacco products and released by combustion of nitrogen-containing organic materials.Pseudomonas: A genus of gram-negative, aerobic, rod-shaped bacteria widely distributed in nature. Some species are pathogenic for humans, animals, and plants.Hydrolysis: The process of cleaving a chemical compound by the addition of a molecule of water.KetonesHafnia alvei: The type species for the genus HAFNIA. It is distinguished from other biochemically similar bacteria by its lack of acid production on media containing sucrose. (From Bergey's Manual of Determinative Bacteriology, 9th ed)PhenazinesIvermectin: A mixture of mostly avermectin H2B1a (RN 71827-03-7) with some avermectin H2B1b (RN 70209-81-3), which are macrolides from STREPTOMYCES avermitilis. It binds glutamate-gated chloride channel to cause increased permeability and hyperpolarization of nerve and muscle cells. It also interacts with other CHLORIDE CHANNELS. It is a broad spectrum antiparasitic that is active against microfilariae of ONCHOCERCA VOLVULUS but not the adult form.Trichomes: Hair-like extensions on specialized epidermal surfaces of plants which protect against damage from insects, animals, light degradation and fungal infection. Trichomes may also occur on certain unicellular EUKARYOTES.Phospholipase A2 Inhibitors: Compounds that inhibit or block the activity of a PHOSPHOLIPASE A2 enzyme.Virulence: The degree of pathogenicity within a group or species of microorganisms or viruses as indicated by case fatality rates and/or the ability of the organism to invade the tissues of the host. The pathogenic capacity of an organism is determined by its VIRULENCE FACTORS.Signal Transduction: The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.Structure-Activity Relationship: The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.Withania: A plant genus of the family SOLANACEAE. Members contain withanolides. Withania somnifera is the source of ashwagandha and aswal.Pectobacterium: A genus of gram-negative bacteria in the family ENTEROBACTERIACEAE consisting of species that profusely produce pectinolytic enzymes in plant pathogenesis.Centaurea: A plant genus of the family ASTERACEAE. Members contain 5-methyl-8-hydroxycoumarin. The common name of centaury is more often used for CENTAURIUMAmidohydrolasesLaminaria: A genus of BROWN ALGAE in the family Laminariaceae. Dried pencil-like pieces may be inserted in the cervix where they swell as they absorb moisture, serving as osmotic dilators.Tanacetum: A plant genus of the family ASTERACEAE. Some species of the CHRYSANTHEMUM and the old Pyrethrum genera have been reclassified to this genus. The common name of tansy usually refers to this but also forms part of the common name of other plants such as Tansy Ragwort (SENECIO) and Tansyaster (HAPLOPAPPUS).Substrate Specificity: A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.Molecular Conformation: The characteristic three-dimensional shape of a molecule.Genes, Bacterial: The functional hereditary units of BACTERIA.Repressor Proteins: Proteins which maintain the transcriptional quiescence of specific GENES or OPERONS. Classical repressor proteins are DNA-binding proteins that are normally bound to the OPERATOR REGION of an operon, or the ENHANCER SEQUENCES of a gene until a signal occurs that causes their release.Organosilicon Compounds: Organic compounds that contain silicon as an integral part of the molecule.Plant Leaves: Expanded structures, usually green, of vascular plants, characteristically consisting of a bladelike expansion attached to a stem, and functioning as the principal organ of photosynthesis and transpiration. (American Heritage Dictionary, 2d ed)Apium graveolens: A plant species of the family APIACEAE. The stalks are a food source.Cymarine: A cardiotonic cardiac glycoside found in STROPHANTHUS. The aglycone is STROPHANTHIN.Porifera: The phylum of sponges which are sessile, suspension-feeding, multicellular animals that utilize flagellated cells called choanocytes to circulate water. Most are hermaphroditic. They are probably an early evolutionary side branch that gave rise to no other group of animals. Except for about 150 freshwater species, sponges are marine animals. They are a source of ALKALOIDS; STEROLS; and other complex molecules useful in medicine and biological research.Aryldialkylphosphatase: An enzyme which catalyzes the hydrolysis of an aryl-dialkyl phosphate to form dialkyl phosphate and an aryl alcohol. It can hydrolyze a broad spectrum of organophosphate substrates and a number of aromatic carboxylic acid esters. It may also mediate an enzymatic protection of LOW DENSITY LIPOPROTEINS against oxidative modification and the consequent series of events leading to ATHEROMA formation. The enzyme was previously regarded to be identical with Arylesterase (EC 188.8.131.52).Rhodococcus: A bacterial genus of the order ACTINOMYCETALES.Carbon-Sulfur Ligases: Enzymes that catalyze the joining of two molecules by the formation of a carbon-sulfur bond. EC 6.2.Kinetics: The rate dynamics in chemical or physical systems.Countercurrent Distribution: A method of separation of two or more substances by repeated distribution between two immiscible liquid phases that move past each other in opposite directions. It is a form of liquid-liquid chromatography. (Stedman, 25th ed)Plant Roots: The usually underground portions of a plant that serve as support, store food, and through which water and mineral nutrients enter the plant. (From American Heritage Dictionary, 1982; Concise Dictionary of Biology, 1990)Adipates: Derivatives of adipic acid. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain a 1,6-carboxy terminated aliphatic structure.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.