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.

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.

Cyclic esters of acylated BUTYRIC ACID containing four carbons in the ring.

Homoserine is a non-proteinogenic amino acid, an intermediate in the biosynthesis of certain amino acids and other metabolites, with structural formula (2S)-2-amino-1-hydroxybutane-1-carboxylic acid.

Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.

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.

Enzymes that catalyze the cleavage of a carbon-sulfur bond by means other than hydrolysis or oxidation. EC 4.4.

Cyclic esters of hydroxy carboxylic acids, containing a 1-oxacycloalkan-2-one structure. Large cyclic lactones of over a dozen atoms are MACROLIDES.

Proteins found in any species of bacterium.

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.

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.

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.

Physiological processes and properties of BACTERIA.

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.

Antibiotic pigment produced by Pseudomonas aeruginosa.

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.

Those components of an organism that determine its capacity to cause disease but are not required for its viability per se. Two classes have been characterized: TOXINS, BIOLOGICAL and surface adhesion molecules that effect the ability of the microorganism to invade and colonize a host. (From Davis et al., Microbiology, 4th ed. p486)

Diffusible gene products that act on homologous or heterologous molecules of viral or cellular DNA to regulate the expression of proteins.

A colorless liquid extracted from oils of plants such as citronella, neroli, cyclamen, and tuberose. It is an intermediate step in the biological synthesis of cholesterol from mevalonic acid in vertebrates. It has a delicate odor and is used in perfumery. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)

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.

The etiologic agent of CHOLERA.

A genus of gram-negative bacteria in the family ENTEROBACTERIACEAE consisting of species that profusely produce pectinolytic enzymes in plant pathogenesis.

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.

Compounds with a 5-membered ring of four carbons and an oxygen. They are aromatic heterocycles. The reduced form is tetrahydrofuran.

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.

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.

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.

Infections with bacteria of the genus PSEUDOMONAS.

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.