Pseudomonas syringae: A species of gram-negative, fluorescent, phytopathogenic bacteria in the genus PSEUDOMONAS. It is differentiated into approximately 50 pathovars with different plant pathogenicities and host specificities.Pseudomonas: A genus of gram-negative, aerobic, rod-shaped bacteria widely distributed in nature. Some species are pathogenic for humans, animals, and plants.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.Plant Diseases: Diseases of plants.Indenes: A family of fused-ring hydrocarbons isolated from coal tar that act as intermediates in various chemical reactions and are used in the production of coumarone-indene resins.Pseudomonas Infections: Infections with bacteria of the genus PSEUDOMONAS.Lycopersicon esculentum: A plant species of the family SOLANACEAE, native of South America, widely cultivated for their edible, fleshy, usually red fruit.Pseudomonas fluorescens: A species of nonpathogenic fluorescent bacteria found in feces, sewage, soil, and water, and which liquefy gelatin.Salicylic Acid: A compound obtained from the bark of the white willow and wintergreen leaves. It has bacteriostatic, fungicidal, and keratolytic actions.Bacterial Proteins: Proteins found in any species of bacterium.Pseudomonas putida: A species of gram-negative, aerobic bacteria isolated from soil and water as well as clinical specimens. Occasionally it is an opportunistic pathogen.Arabidopsis: A plant genus of the family BRASSICACEAE that contains ARABIDOPSIS PROTEINS and MADS DOMAIN PROTEINS. The species A. thaliana is used for experiments in classical plant genetics as well as molecular genetic studies in plant physiology, biochemistry, and development.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)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.Genes, Bacterial: The functional hereditary units of BACTERIA.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.Arabidopsis Proteins: Proteins that originate from plants species belonging to the genus ARABIDOPSIS. The most intensely studied species of Arabidopsis, Arabidopsis thaliana, is commonly used in laboratory experiments.Gene Expression Regulation, Bacterial: Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.Tobacco: A plant genus of the family SOLANACEAE. Members contain NICOTINE and other biologically active chemicals; its dried leaves are used for SMOKING.Plant Immunity: The inherent or induced capacity of plants to withstand or ward off biological attack by pathogens.Fabaceae: The large family of plants characterized by pods. Some are edible and some cause LATHYRISM or FAVISM and other forms of poisoning. Other species yield useful materials like gums from ACACIA and various LECTINS like PHYTOHEMAGGLUTININS from PHASEOLUS. Many of them harbor NITROGEN FIXATION bacteria on their roots. Many but not all species of "beans" belong to this family.Gene Expression Regulation, Plant: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in plants.Oxylipins: Eighteen-carbon cyclopentyl polyunsaturated fatty acids derived from ALPHA-LINOLENIC ACID via an oxidative pathway analogous to the EICOSANOIDS in animals. Biosynthesis is inhibited by SALICYLATES. A key member, jasmonic acid of PLANTS, plays a similar role to ARACHIDONIC ACID in animals.Actinidia: A plant species of the family ACTINIDIACEAE, order Theales.Disease Resistance: The capacity of an organism to defend itself against pathological processes or the agents of those processes. This most often involves innate immunity whereby the organism responds to pathogens in a generic way. The term disease resistance is used most frequently when referring to plants.Phaseolus: A plant genus in the family FABACEAE which is the source of edible beans and the lectin PHYTOHEMAGGLUTININS.Cyclopentanes: A group of alicyclic hydrocarbons with the general formula R-C5H9.Plants, Genetically Modified: PLANTS, or their progeny, whose GENOME has been altered by GENETIC ENGINEERING.DNA, Bacterial: Deoxyribonucleic acid that makes up the genetic material of bacteria.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.Plant Proteins: Proteins found in plants (flowers, herbs, shrubs, trees, etc.). The concept does not include proteins found in vegetables for which VEGETABLE PROTEINS is available.Pseudomonas Phages: Viruses whose host is Pseudomonas. A frequently encountered Pseudomonas phage is BACTERIOPHAGE PHI 6.Botrytis: A mitosporic Leotiales fungal genus of plant pathogens. It has teleomorphs in the genus Botryotina.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.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)Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Immunity, Innate: The capacity of a normal organism to remain unaffected by microorganisms and their toxins. It results from the presence of naturally occurring ANTI-INFECTIVE AGENTS, constitutional factors such as BODY TEMPERATURE and immediate acting immune cells such as NATURAL KILLER CELLS.Host-Pathogen Interactions: The interactions between a host and a pathogen, usually resulting in disease.Mutagenesis, Insertional: Mutagenesis where the mutation is caused by the introduction of foreign DNA sequences into a gene or extragenic sequence. This may occur spontaneously in vivo or be experimentally induced in vivo or in vitro. Proviral DNA insertions into or adjacent to a cellular proto-oncogene can interrupt GENETIC TRANSLATION of the coding sequences or interfere with recognition of regulatory elements and cause unregulated expression of the proto-oncogene resulting in tumor formation.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.Alginates: Salts of alginic acid that are extracted from marine kelp and used to make dental impressions and as absorbent material for surgical dressings.Erwinia: A genus of gram-negative, facultatively anaerobic, rod-shaped bacteria whose organisms are associated with plants as pathogens, saprophytes, or as constituents of the epiphytic flora.Plants, Medicinal: Plants whose roots, leaves, seeds, bark, or other constituent parts possess therapeutic, tonic, purgative, curative or other pharmacologic attributes, when administered to man or animals.Ornithine: An amino acid produced in the urea cycle by the splitting off of urea from arginine.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.Plasmids: 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.Pseudomonas stutzeri: A species of gram-negative bacteria in the genus PSEUDOMONAS, containing multiple genomovars. It is distinguishable from other pseudomonad species by its ability to use MALTOSE and STARCH as sole carbon and energy sources. It can degrade ENVIRONMENTAL POLLUTANTS and has been used as a model organism to study denitrification.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.DNA Transposable Elements: Discrete segments of DNA which can excise and reintegrate to another site in the genome. Most are inactive, i.e., have not been found to exist outside the integrated state. DNA transposable elements include bacterial IS (insertion sequence) elements, Tn elements, the maize controlling elements Ac and Ds, Drosophila P, gypsy, and pogo elements, the human Tigger elements and the Tc and mariner elements which are found throughout the animal kingdom.Oomycetes: Eukaryotes in the group STRAMENOPILES, formerly considered FUNGI, whose exact taxonomic level is unsettled. Many consider Oomycetes (Oomycota) a phylum in the kingdom Stramenopila, or alternatively, as Pseudofungi in the phylum Heterokonta of the kingdom Chromista. They are morphologically similar to fungi but have no close phylogenetic relationship to them. Oomycetes are found in both fresh and salt water as well as in terrestrial environments. (Alexopoulos et al., Introductory Mycology, 4th ed, pp683-4). They produce flagellated, actively motile spores (zoospores) that are pathogenic to many crop plants and FISHES.Ice: The solid substance formed by the FREEZING of water.Sequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.Peptides, Cyclic: Peptides whose amino and carboxy ends are linked together with a peptide bond forming a circular chain. Some of them are ANTI-INFECTIVE AGENTS. Some of them are biosynthesized non-ribosomally (PEPTIDE BIOSYNTHESIS, NON-RIBOSOMAL).Siderophores: Low-molecular-weight compounds produced by microorganisms that aid in the transport and sequestration of ferric iron. (The Encyclopedia of Molecular Biology, 1994)Soybeans: An annual legume. The SEEDS of this plant are edible and used to produce a variety of SOY FOODS.Operon: In bacteria, a group of metabolically related genes, with a common promoter, whose transcription into a single polycistronic MESSENGER RNA is under the control of an OPERATOR REGION.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)Bacterial Outer Membrane Proteins: Proteins isolated from the outer membrane of Gram-negative bacteria.Xanthomonas campestris: A species of gram-negative, aerobic bacteria that is pathogenic for plants.Ethylenes: Derivatives of ethylene, a simple organic gas of biological origin with many industrial and biological use.Bacterial Toxins: Toxic substances formed in or elaborated by bacteria; they are usually proteins with high molecular weight and antigenicity; some are used as antibiotics and some to skin test for the presence of or susceptibility to certain diseases.Genome, Bacterial: The genetic complement of a BACTERIA as represented in its DNA.Antibiosis: A natural association between organisms that is detrimental to at least one of them. This often refers to the production of chemicals by one microorganism that is harmful to another.Rhamnose: A methylpentose whose L- isomer is found naturally in many plant glycosides and some gram-negative bacterial lipopolysaccharides.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.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Exotoxins: Toxins produced, especially by bacterial or fungal cells, and released into the culture medium or environment.Genes, Plant: The functional hereditary units of PLANTS.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.Sigma Factor: A protein which is a subunit of RNA polymerase. It effects initiation of specific RNA chains from DNA.Syringa: A plant genus of the family OLEACEAE. Oleuropein has been identified in the stem bark.Pyrus: A plant genus of the family ROSACEAE known for the edible fruit.Anti-Bacterial Agents: Substances that reduce the growth or reproduction of BACTERIA.Alternaria: A mitosporic Loculoascomycetes fungal genus including several plant pathogens and at least one species which produces a highly phytotoxic antibiotic. Its teleomorph is Lewia.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)Fructans: Polysaccharides composed of D-fructose units.Pest Control, Biological: Use of naturally-occuring or genetically-engineered organisms to reduce or eliminate populations of pests.Erwinia amylovora: A species of gram-negative bacteria, in the genus ERWINIA, causing a necrotic disease of plants.Flagellin: A protein with a molecular weight of 40,000 isolated from bacterial flagella. At appropriate pH and salt concentration, three flagellin monomers can spontaneously reaggregate to form structures which appear identical to intact flagella.Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.Aesculus: A plant genus of the family HIPPOCASTANACEAE (or SAPINDACEAE by some) that contains antimicrobial protein 1 and escin. A. hippocastanum is used in folk medicine for treating chronic venous insufficiency.Plants, Toxic: Plants or plant parts which are harmful to man or other animals.Ornithine Carbamoyltransferase: A urea cycle enzyme that catalyzes the formation of orthophosphate and L-citrulline (CITRULLINE) from CARBAMOYL PHOSPHATE and L-ornithine (ORNITHINE). Deficiency of this enzyme may be transmitted as an X-linked trait. EC 2.1.3.3.Restriction Mapping: Use of restriction endonucleases to analyze and generate a physical map of genomes, genes, or other segments of DNA.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.Glucuronic Acid: A sugar acid formed by the oxidation of the C-6 carbon of GLUCOSE. In addition to being a key intermediate metabolite of the uronic acid pathway, glucuronic acid also plays a role in the detoxification of certain drugs and toxins by conjugating with them to form GLUCURONIDES.Amino Acids: 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.Mangifera: A plant genus of the family ANACARDIACEAE best known for the edible fruit.Hexuronic Acids: Term used to designate tetrahydroxy aldehydic acids obtained by oxidation of hexose sugars, i.e. glucuronic acid, galacturonic acid, etc. Historically, the name hexuronic acid was originally given to ascorbic acid.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.Open Reading Frames: A sequence of successive nucleotide triplets that are read as CODONS specifying AMINO ACIDS and begin with an INITIATOR CODON and end with a stop codon (CODON, TERMINATOR).Corylus: A plant genus of the family BETULACEAE known for the edible nuts.Culture Media: Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.Cosmids: Plasmids containing at least one cos (cohesive-end site) of PHAGE LAMBDA. They are used as cloning vehicles.Glucans: Polysaccharides composed of repeating glucose units. They can consist of branched or unbranched chains in any linkages.Petroselinum: A plant genus of the family APIACEAE used for flavoring food.AzetinesPlant Stomata: Closable openings in the epidermis of plants on the underside of leaves. They allow the exchange of gases between the internal tissues of the plant and the outside atmosphere.Pseudomonadaceae: A family of gram-negative bacteria usually found in soil or water and including many plant pathogens and a few animal pathogens.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.Capsicum: A plant genus of the family SOLANACEAE. The hot peppers yield CAPSAICIN, which activates VANILLOID RECEPTORS. Several varieties have sweet or pungent edible fruits that are used as vegetables when fresh and spices when the pods are dried.ADP Ribose Transferases: Enzymes that transfer the ADP-RIBOSE group of NAD or NADP to proteins or other small molecules. Transfer of ADP-ribose to water (i.e., hydrolysis) is catalyzed by the NADASES. The mono(ADP-ribose)transferases transfer a single ADP-ribose. POLY(ADP-RIBOSE) POLYMERASES transfer multiple units of ADP-ribose to protein targets, building POLY ADENOSINE DIPHOSPHATE RIBOSE in linear or branched chains.Antarctic Regions: The continent lying around the South Pole and the southern waters of the Atlantic, Pacific, and Indian Oceans. It includes the Falkland Islands Dependencies. (From Webster's New Geographical Dictionary, 1988, p55)Host Specificity: The properties of a pathogen that makes it capable of infecting one or more specific hosts. The pathogen can include PARASITES as well as VIRUSES; BACTERIA; FUNGI; or PLANTS.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.Species Specificity: The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.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.Promoter Regions, Genetic: DNA sequences which are recognized (directly or indirectly) and bound by a DNA-dependent RNA polymerase during the initiation of transcription. Highly conserved sequences within the promoter include the Pribnow box in bacteria and the TATA BOX in eukaryotes.Drug Resistance, Microbial: The ability of microorganisms, especially bacteria, to resist or to become tolerant to chemotherapeutic agents, antimicrobial agents, or antibiotics. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).Genomic Islands: Distinct units in some bacterial, bacteriophage or plasmid GENOMES that are types of MOBILE GENETIC ELEMENTS. Encoded in them are a variety of fitness conferring genes, such as VIRULENCE FACTORS (in "pathogenicity islands or islets"), ANTIBIOTIC RESISTANCE genes, or genes required for SYMBIOSIS (in "symbiosis islands or islets"). They range in size from 10 - 500 kilobases, and their GC CONTENT and CODON usage differ from the rest of the genome. They typically contain an INTEGRASE gene, although in some cases this gene has been deleted resulting in "anchored genomic islands".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.Microbial Sensitivity Tests: Any tests that demonstrate the relative efficacy of different chemotherapeutic agents against specific microorganisms (i.e., bacteria, fungi, viruses).Polysaccharide-Lyases: A group of carbon-oxygen lyases. These enzymes catalyze the breakage of a carbon-oxygen bond in polysaccharides leading to an unsaturated product and the elimination of an alcohol. EC 4.2.2.Fenthion: Potent cholinesterase inhibitor used as an insecticide and acaricide.Plant Growth Regulators: Any of the hormones produced naturally in plants and active in controlling growth and other functions. There are three primary classes: auxins, cytokinins, and gibberellins.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)Temperature: The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.Serology: The study of serum, especially of antigen-antibody reactions in vitro.Gene Deletion: A genetic rearrangement through loss of segments of DNA or RNA, bringing sequences which are normally separated into close proximity. This deletion may be detected using cytogenetic techniques and can also be inferred from the phenotype, indicating a deletion at one specific locus.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.DNA Primers: Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques.RNA Polymerase Sigma 54: A DNA-directed RNA polymerase found in BACTERIA. It is a holoenzyme that consists of multiple subunits including sigma factor 54.Colony Count, Microbial: Enumeration by direct count of viable, isolated bacterial, archaeal, or fungal CELLS or SPORES capable of growth on solid CULTURE MEDIA. The method is used routinely by environmental microbiologists for quantifying organisms in AIR; FOOD; and WATER; by clinicians for measuring patients' microbial load; and in antimicrobial drug testing.Gene Order: The sequential location of genes on a chromosome.Cystic Fibrosis: An autosomal recessive genetic disease of the EXOCRINE GLANDS. It is caused by mutations in the gene encoding the CYSTIC FIBROSIS TRANSMEMBRANE CONDUCTANCE REGULATOR expressed in several organs including the LUNG, the PANCREAS, the BILIARY SYSTEM, and the SWEAT GLANDS. Cystic fibrosis is characterized by epithelial secretory dysfunction associated with ductal obstruction resulting in AIRWAY OBSTRUCTION; chronic RESPIRATORY INFECTIONS; PANCREATIC INSUFFICIENCY; maldigestion; salt depletion; and HEAT PROSTRATION.Transcription, Genetic: The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.Peronospora: A genus of OOMYCETES in the family Peronosporaceae. Most species are obligatory parasites and many are plant pathogens.O Antigens: The lipopolysaccharide-protein somatic antigens, usually from gram-negative bacteria, important in the serological classification of enteric bacilli. The O-specific chains determine the specificity of the O antigens of a given serotype. O antigens are the immunodominant part of the lipopolysaccharide molecule in the intact bacterial cell. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)RNA, Plant: Ribonucleic acid in plants having regulatory and catalytic roles as well as involvement in protein synthesis.Pyocyanine: Antibiotic pigment produced by Pseudomonas aeruginosa.Pectobacterium chrysanthemi: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria that causes vascular wilts on a wide range of plant species. It was formerly named Erwinia chrysanthemi.Chromosome Mapping: Any method used for determining the location of and relative distances between genes on a chromosome.Fimbriae, Bacterial: Thin, hairlike appendages, 1 to 20 microns in length and often occurring in large numbers, present on the cells of gram-negative bacteria, particularly Enterobacteriaceae and Neisseria. Unlike flagella, they do not possess motility, but being protein (pilin) in nature, they possess antigenic and hemagglutinating properties. They are of medical importance because some fimbriae mediate the attachment of bacteria to cells via adhesins (ADHESINS, BACTERIAL). Bacterial fimbriae refer to common pili, to be distinguished from the preferred use of "pili", which is confined to sex pili (PILI, SEX).Biosynthetic Pathways: Sets of enzymatic reactions occurring in organisms and that form biochemicals by making new covalent bonds.Transcription Factors: Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.Salicylates: The salts or esters of salicylic acids, or salicylate esters of an organic acid. Some of these have analgesic, antipyretic, and anti-inflammatory activities by inhibiting prostaglandin synthesis.Bacteria: One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.Biodegradation, Environmental: Elimination of ENVIRONMENTAL POLLUTANTS; PESTICIDES and other waste using living organisms, usually involving intervention of environmental or sanitation engineers.Seedling: Very young plant after GERMINATION of SEEDS.Regulon: In eukaryotes, a genetic unit consisting of a noncontiguous group of genes under the control of a single regulator gene. In bacteria, regulons are global regulatory systems involved in the interplay of pleiotropic regulatory domains and consist of several OPERONS.ThiadiazolesReceptors, Pattern Recognition: A large family of cell surface receptors that bind conserved molecular structures (PAMPS) present in pathogens. They play important roles in host defense by mediating cellular responses to pathogens.Cell Death: The termination of the cell's ability to carry out vital functions such as metabolism, growth, reproduction, responsiveness, and adaptability.Chromosomes, Bacterial: Structures within the nucleus of bacterial cells consisting of or containing DNA, which carry genetic information essential to the cell.Carboxylic Ester Hydrolases: Enzymes which catalyze the hydrolysis of carboxylic acid esters with the formation of an alcohol and a carboxylic acid anion.Pseudomonas mendocina: A species of gram-negative bacteria in the genus PSEUDOMONAS, which is found in SOIL and WATER.Protein Transport: The process of moving proteins from one cellular compartment (including extracellular) to another by various sorting and transport mechanisms such as gated transport, protein translocation, and vesicular transport.Bacterial Secretion Systems: In GRAM NEGATIVE BACTERIA, multiprotein complexes that function to translocate pathogen protein effector molecules across the bacterial cell envelope, often directly into the host. These effectors are involved in producing surface structures for adhesion, bacterial motility, manipulation of host functions, modulation of host defense responses, and other functions involved in facilitating survival of the pathogen. Several of the systems have homologous components functioning similarly in GRAM POSITIVE BACTERIA.Indoleacetic Acids: Acetic acid derivatives of the heterocyclic compound indole. (Merck Index, 11th ed)DNA-Binding Proteins: Proteins which bind to DNA. The family includes proteins which bind to both double- and single-stranded DNA and also includes specific DNA binding proteins in serum which can be used as markers for malignant diseases.Oxygenases: Oxidases that specifically introduce DIOXYGEN-derived oxygen atoms into a variety of organic molecules.Recombinant Fusion Proteins: Recombinant proteins produced by the GENETIC TRANSLATION of fused genes formed by the combination of NUCLEIC ACID REGULATORY SEQUENCES of one or more genes with the protein coding sequences of one or more genes.Xanthomonas vesicatoria: A species of gram-negative bacteria, in the genus XANTHOMONAS, causing disease in TOMATO and pepper crops.Polysaccharides, Bacterial: Polysaccharides found in bacteria and in capsules thereof.Sequence Homology, Nucleic Acid: The sequential correspondence of nucleotides in one nucleic acid molecule with those of another nucleic acid molecule. Sequence homology is an indication of the genetic relatedness of different organisms and gene function.Plants, Edible: An organism of the vegetable kingdom suitable by nature for use as a food, especially by human beings. Not all parts of any given plant are edible but all parts of edible plants have been known to figure as raw or cooked food: leaves, roots, tubers, stems, seeds, buds, fruits, and flowers. The most commonly edible parts of plants are FRUIT, usually sweet, fleshy, and succulent. Most edible plants are commonly cultivated for their nutritional value and are referred to as VEGETABLES.Conjugation, Genetic: A parasexual process in BACTERIA; ALGAE; FUNGI; and ciliate EUKARYOTA for achieving exchange of chromosome material during fusion of two cells. In bacteria, this is a uni-directional transfer of genetic material; in protozoa it is a bi-directional exchange. In algae and fungi, it is a form of sexual reproduction, with the union of male and female gametes.RNA, Bacterial: Ribonucleic acid in bacteria having regulatory and catalytic roles as well as involvement in protein synthesis.Polymerase Chain Reaction: In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.Copper: A heavy metal trace element with the atomic symbol Cu, atomic number 29, and atomic weight 63.55.Rhizobium: A genus of gram-negative, aerobic, rod-shaped bacteria that activate PLANT ROOT NODULATION in leguminous plants. Members of this genus are nitrogen-fixing and common soil inhabitants.Mutagenesis: Process of generating a genetic MUTATION. It may occur spontaneously or be induced by MUTAGENS.Fungi: A kingdom of eukaryotic, heterotrophic organisms that live parasitically as saprobes, including MUSHROOMS; YEASTS; smuts, molds, etc. They reproduce either sexually or asexually, and have life cycles that range from simple to complex. Filamentous fungi, commonly known as molds, refer to those that grow as multicellular colonies.Iron: A metallic element with atomic symbol Fe, atomic number 26, and atomic weight 55.85. It is an essential constituent of HEMOGLOBINS; CYTOCHROMES; and IRON-BINDING PROTEINS. It plays a role in cellular redox reactions and in the transport of OXYGEN.Glucosinolates: Substituted thioglucosides. They are found in rapeseed (Brassica campestris) products and related cruciferae. They are metabolized to a variety of toxic products which are most likely the cause of hepatocytic necrosis in animals and humans.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).Dipeptides: Peptides composed of two amino acid units.Streptomycin: An antibiotic produced by the soil actinomycete Streptomyces griseus. It acts by inhibiting the initiation and elongation processes during protein synthesis.Fosfomycin: An antibiotic produced by Streptomyces fradiae.DNA, Plant: Deoxyribonucleic acid that makes up the genetic material of plants.Phenylalanine Ammonia-Lyase: An enzyme that catalyzes the deamination of PHENYLALANINE to form trans-cinnamate and ammonia.Xanthomonas: A genus in the family XANTHOMONADACEAE whose cells produce a yellow pigment (Gr. xanthos - yellow). It is pathogenic to plants.Ketoglutaric Acids: A family of compounds containing an oxo group with the general structure of 1,5-pentanedioic acid. (From Lehninger, Principles of Biochemistry, 1982, p442)Gene Expression Profiling: The determination of the pattern of genes expressed at the level of GENETIC TRANSCRIPTION, under specific circumstances or in a specific cell.Defensins: Family of antimicrobial peptides that have been identified in humans, animals, and plants. They are thought to play a role in host defenses against infections, inflammation, wound repair, and acquired immunity.Mixed Function Oxygenases: Widely distributed enzymes that carry out oxidation-reduction reactions in which one atom of the oxygen molecule is incorporated into the organic substrate; the other oxygen atom is reduced and combined with hydrogen ions to form water. They are also known as monooxygenases or hydroxylases. These reactions require two substrates as reductants for each of the two oxygen atoms. There are different classes of monooxygenases depending on the type of hydrogen-providing cosubstrate (COENZYMES) required in the mixed-function oxidation.CitratesOxidoreductases: The class of all enzymes catalyzing oxidoreduction reactions. The substrate that is oxidized is regarded as a hydrogen donor. The systematic name is based on donor:acceptor oxidoreductase. The recommended name will be dehydrogenase, wherever this is possible; as an alternative, reductase can be used. Oxidase is only used in cases where O2 is the acceptor. (Enzyme Nomenclature, 1992, p9)Two-Hybrid System Techniques: Screening techniques first developed in yeast to identify genes encoding interacting proteins. Variations are used to evaluate interplay between proteins and other molecules. Two-hybrid techniques refer to analysis for protein-protein interactions, one-hybrid for DNA-protein interactions, three-hybrid interactions for RNA-protein interactions or ligand-based interactions. Reverse n-hybrid techniques refer to analysis for mutations or other small molecules that dissociate known interactions.Fruit: The fleshy or dry ripened ovary of a plant, enclosing the seed or seeds.Substrate Specificity: A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.Ascomycota: A phylum of fungi which have cross-walls or septa in the mycelium. The perfect state is characterized by the formation of a saclike cell (ascus) containing ascospores. Most pathogenic fungi with a known perfect state belong to this phylum.Tobramycin: An aminoglycoside, broad-spectrum antibiotic produced by Streptomyces tenebrarius. It is effective against gram-negative bacteria, especially the PSEUDOMONAS species. It is a 10% component of the antibiotic complex, NEBRAMYCIN, produced by the same species.Bacterial Adhesion: Physicochemical property of fimbriated (FIMBRIAE, BACTERIAL) and non-fimbriated bacteria of attaching to cells, tissue, and nonbiological surfaces. It is a factor in bacterial colonization and pathogenicity.Flagella: A whiplike motility appendage present on the surface cells. Prokaryote flagella are composed of a protein called FLAGELLIN. Bacteria can have a single flagellum, a tuft at one pole, or multiple flagella covering the entire surface. In eukaryotes, flagella are threadlike protoplasmic extensions used to propel flagellates and sperm. Flagella have the same basic structure as CILIA but are longer in proportion to the cell bearing them and present in much smaller numbers. (From King & Stansfield, A Dictionary of Genetics, 4th ed)Nucleic Acid Hybridization: Widely used technique which exploits the ability of complementary sequences in single-stranded DNAs or RNAs to pair with each other to form a double helix. Hybridization can take place between two complimentary DNA sequences, between a single-stranded DNA and a complementary RNA, or between two RNA sequences. The technique is used to detect and isolate specific sequences, measure homology, or define other characteristics of one or both strands. (Kendrew, Encyclopedia of Molecular Biology, 1994, p503)