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.Gram-Negative Bacterial Infections: Infections caused by bacteria that show up as pink (negative) when treated by the gram-staining method.Electronic Waste: Discarded electronic devices containing valuable and sometimes hazardous materials such as LEAD, NICKEL, CADMIUM, and MERCURY. (from accessed 4/25/2010)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.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.Encyclopedias as Topic: Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)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)Anti-Bacterial Agents: Substances that reduce the growth or reproduction of BACTERIA.Phenylalanine Hydroxylase: An enzyme of the oxidoreductase class that catalyzes the formation of L-TYROSINE, dihydrobiopterin, and water from L-PHENYLALANINE, tetrahydrobiopterin, and oxygen. Deficiency of this enzyme may cause PHENYLKETONURIAS and PHENYLKETONURIA, MATERNAL. EC An essential aromatic amino acid that is a precursor of MELANIN; DOPAMINE; noradrenalin (NOREPINEPHRINE), and THYROXINE.Phenylketonurias: A group of autosomal recessive disorders marked by a deficiency of the hepatic enzyme PHENYLALANINE HYDROXYLASE or less frequently by reduced activity of DIHYDROPTERIDINE REDUCTASE (i.e., atypical phenylketonuria). Classical phenylketonuria is caused by a severe deficiency of phenylalanine hydroxylase and presents in infancy with developmental delay; SEIZURES; skin HYPOPIGMENTATION; ECZEMA; and demyelination in the central nervous system. (From Adams et al., Principles of Neurology, 6th ed, p952).Ribosome Subunits, Small, Eukaryotic: The small subunit of the 80s ribosome of eukaryotes. It is composed of the 18S RIBOSOMAL RNA and 32 different RIBOSOMAL PROTEINS.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.Cupriavidus: A genus of gram-negative, aerobic, rod-shaped bacteria, in the family BURKHOLDERIACEAE, that are mobile by means of peritrichous FLAGELLA. The genus was formerly called Wautersia and species in this genus were formerly in the genus RALSTONIA.Prophages: Genomes of temperate BACTERIOPHAGES integrated into the DNA of their bacterial host cell. The prophages can be duplicated for many cell generations until some stimulus induces its activation and virulence.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.FuraldehydeMagnetic 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).Francisella tularensis: The etiologic agent of TULAREMIA in man and other warm-blooded animals.Crystallography, X-Ray: The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Pyridoxal Phosphate: This is the active form of VITAMIN B 6 serving as a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid. During transamination of amino acids, pyridoxal phosphate is transiently converted into pyridoxamine phosphate (PYRIDOXAMINE).Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Metals: Electropositive chemical elements characterized by ductility, malleability, luster, and conductance of heat and electricity. They can replace the hydrogen of an acid and form bases with hydroxyl radicals. (Grant & Hackh's Chemical Dictionary, 5th ed)Biopterin: A natural product that has been considered as a growth factor for some insects.Patents as Topic: Exclusive legal rights or privileges applied to inventions, plants, etc.Agrochemicals: Chemicals used in agriculture. These include pesticides, fumigants, fertilizers, plant hormones, steroids, antibiotics, mycotoxins, etc.Ecotoxicology: The study of ENVIRONMENTAL POLLUTION and the toxic effects of ENVIRONMENTAL POLLUTANTS on the ECOSYSTEM. The term was coined by Truhaut in 1969.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.Inventions: A novel composition, device, or process, independently conceived de novo or derived from a pre-existing model.Actinobacteria: Class of BACTERIA with diverse morphological properties. Strains of Actinobacteria show greater than 80% 16S rDNA/rRNA sequence similarity among each other and also the presence of certain signature nucleotides. (Stackebrandt E. et al, Int. J. Syst. Bacteriol. (1997) 47:479-491)X-Ray Absorption Spectroscopy: Analysis of the energy absorbed across a spectrum of x-ray energies/wavelengths to determine the chemical structure and electronic states of the absorbing medium.Copper: A heavy metal trace element with the atomic symbol Cu, atomic number 29, and atomic weight 63.55.X-Rays: Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard X-rays are the higher energy, shorter wavelength X-rays. Soft x-rays or Grenz rays are less energetic and longer in wavelength. The short wavelength end of the X-ray spectrum overlaps the GAMMA RAYS wavelength range. The distinction between gamma rays and X-rays is based on their radiation source.Computer Security: Protective measures against unauthorized access to or interference with computer operating systems, telecommunications, or data structures, especially the modification, deletion, destruction, or release of data in computers. It includes methods of forestalling interference by computer viruses or so-called computer hackers aiming to compromise stored data.Confidentiality: The privacy of information and its protection against unauthorized disclosure.Privacy: The state of being free from intrusion or disturbance in one's private life or affairs. (Random House Unabridged Dictionary, 2d ed, 1993)Deuterium: Deuterium. The stable isotope of hydrogen. It has one neutron and one proton in the nucleus.Isotopes: Atomic species differing in mass number but having the same atomic number. (Grant & Hackh's Chemical Dictionary, 5th ed)Portal Vein: A short thick vein formed by union of the superior mesenteric vein and the splenic vein.Aminopeptidases: A subclass of EXOPEPTIDASES that act on the free N terminus end of a polypeptide liberating a single amino acid residue. EC 3.4.11.Leucyl Aminopeptidase: A zinc containing enzyme of the hydrolase class that catalyzes the removal of the N-terminal amino acid from most L-peptides, particularly those with N-terminal leucine residues but not those with N-terminal lysine or arginine residues. This occurs in tissue cell cytosol, with high activity in the duodenum, liver, and kidney. The activity of this enzyme is commonly assayed using a leucine arylamide chromogenic substrate such as leucyl beta-naphthylamide.Antigens, CD13: Zinc-binding metalloproteases that are members of the type II integral membrane metalloproteases. They are expressed by GRANULOCYTES; MONOCYTES; and their precursors as well as by various non-hematopoietic cells. They release an N-terminal amino acid from a peptide, amide or arylamide.Glutamyl Aminopeptidase: A ZINC-dependent membrane-bound aminopeptidase that catalyzes the N-terminal peptide cleavage of GLUTAMATE (and to a lesser extent ASPARTATE). The enzyme appears to play a role in the catabolic pathway of the RENIN-ANGIOTENSIN SYSTEM.Cystinyl Aminopeptidase: A zinc-containing sialoglycoprotein that is used to study aminopeptidase activity in the pathogenesis of hypertension. EC 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.PubMed: A bibliographic database that includes MEDLINE as its primary subset. It is produced by the National Center for Biotechnology Information (NCBI), part of the NATIONAL LIBRARY OF MEDICINE. PubMed, which is searchable through NLM's Web site, also includes access to additional citations to selected life sciences journals not in MEDLINE, and links to other resources such as the full-text of articles at participating publishers' Web sites, NCBI's molecular biology databases, and PubMed Central.Periodicals as Topic: A publication issued at stated, more or less regular, intervals.BooksPublishing: "The business or profession of the commercial production and issuance of literature" (Webster's 3d). It includes the publisher, publication processes, editing and editors. Production may be by conventional printing methods or by electronic publishing.MEDLINE: The premier bibliographic database of the NATIONAL LIBRARY OF MEDICINE. MEDLINE® (MEDLARS Online) is the primary subset of PUBMED and can be searched on NLM's Web site in PubMed or the NLM Gateway. MEDLINE references are indexed with MEDICAL SUBJECT HEADINGS (MeSH).Serial Publications: Publications in any medium issued in successive parts bearing numerical or chronological designations and intended to be continued indefinitely. (ALA Glossary of Library and Information Science, 1983, p203)Biological Science Disciplines: All of the divisions of the natural sciences dealing with the various aspects of the phenomena of life and vital processes. The concept includes anatomy and physiology, biochemistry and biophysics, and the biology of animals, plants, and microorganisms. It should be differentiated from BIOLOGY, one of its subdivisions, concerned specifically with the origin and life processes of living organisms.

Effective method for activity assay of lipase from Chromobacterium viscosum. (1/183)

A method was devised for activity assay of the lipase [triacylglycerol acyl-hydrolase, EC] excreted from Chromobacterium viscosum into the culture medium; olive oil emulsified with the aid of Adekatol 45-S-8 (a non-ionic detergent, the ethoxylate of linear sec-alcohols having chain lengths of 10--16 carbon atoms) was used as the substrate. This method was specifically effective for Chromobacterium lipase acitvity assay, and was approximately twice as sensitive as the conventional method, in which polyvinyl alcohol is used for the emulsification of the substrate.  (+info)

Two cases of Chromobacterium violaceum infection after injury in a subtropical region. (2/183)

Chromobacterium violaceum is a gram-negative rod and is isolated from soil and water in tropical and subtropical regions. The species have pigmented and nonpigmented colony types. Infections caused by nonpigmented strains are rare. We report on two cases of infection caused by both pigmented and nonpigmented strains of C. violaceum. Two 24-year-old Korea Airline stewardesses were admitted to Inha University Hospital, Inchon, South Korea, on 9 August 1997, 3 days after an airplane accident in Guam. Both had multiple lacerations on exposed parts of their bodies. There was swelling, tenderness, and pus discharge. The wounds contained many small fragments of stones and weeds. A pigmented strain was isolated from the left hand and a nonpigmented strain was isolated from the left knee of one patient. For the other patient only a nonpigmented strain was isolated from a foot wound. The nonpigmented colonies from the left-knee and the left-foot wounds did not produce any pigment even after an extended period of incubation. The biochemical characteristics were the same for each strain except for oxidase and indole reactions. The pigmented strain was oxidase negative and indole positive, whereas the nonpigmented strains were oxidase positive and indole negative. The patients were successfully treated by debridement and with appropriate antibiotics.  (+info)

Molecular dynamics of microbial lipases as determined from their intrinsic tryptophan fluorescence. (3/183)

We have studied the intrinsic tryptophan fluorescence of the lipases from Chromobacterium viscosum (CVL), Pseudomonas species (PSL), and Rhizopus oryzae (ROL) in aqueous buffer, zwitterionic detergent micelles, and isopropanol-water mixtures. It was the purpose of this study to obtain information about biophysical properties of the respective enzymes under conditions that modulate enzyme activities and stereoselectivities to a significant extent. According to their decay-associated emission spectra, CVL tryptophans are located in the hydrophobic interior of the protein. In contrast, the PSL and ROL tryptophans are probably confined to the core and the surface of the lipase. From the tryptophan lifetime distributions it can be concluded that the conformation of CVL is not much affected by detergent or organic solvent (isopropanol). Accordingly, CVL is enzymatically active in these systems and most active in the presence of isopropanol. In contrast, ROL and PSL show high conformational mobility, depending on the solvent, because their lifetime distributions are very different in the presence and absence of detergent or isopropanol. Time-resolved anisotropy studies provided evidence that the lipases exhibit very high internal molecular flexibility. This peculiar feature of lipases is perhaps the key to the great differences in activity and stereoselectivity observed in different reaction media. Furthermore, information about self-association of the lipases in different solvents could be obtained. PSL, but not CVL and ROL, forms aggregates in water. Lipase aggregation can be reversed by the addition of detergent or isopropanol, which competes for the hydrophobic surface domains of this protein. This dissociation could efficiently contribute to the increase in lipase activity in the presence of a detergent or isopropanol.  (+info)

Cloning, molecular analysis, and expression of the polyhydroxyalkanoic acid synthase (phaC) gene from Chromobacterium violaceum. (4/183)

The polyhydroxyalkanoic acid synthase gene from Chromobacterium violaceum (phaC(Cv)) was cloned and characterized. A 6.3-kb BamHI fragment was found to contain both phaC(Cv) and the polyhydroxyalkanoic acid (PHA)-specific 3-ketothiolase (phaA(Cv)). Escherichia coli strains harboring this fragment produced significant levels of PHA synthase and 3-ketothiolase, as judged by their activities. While C. violaceum accumulated poly(3-hydroxybutyrate) or poly(3-hydroxybutyrate-co-3-hydroxyvalerate) when grown on a fatty acid carbon source, Klebsiella aerogenes and Ralstonia eutropha (formerly Alcaligenes eutrophus), harboring phaC(Cv), accumulated the above-mentioned polymers and, additionally, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) when even-chain-length fatty acids were utilized as the carbon source. This finding suggests that the metabolic environments of these organisms are sufficiently different to alter the product range of the C. violaceum PHA synthase. Neither recombinant E. coli nor recombinant Pseudomonas putida harboring phaC(Cv) accumulated significant levels of PHA. Sequence analysis of the phaC(Cv) product shows homology with several PHA synthases, most notably a 48% identity with that of Alcaligenes latus (GenBank accession no. AAD10274).  (+info)

Chromobacteriosis in a Chinese red panda (Ailurus fulgens styani). (5/183)

An adult Chinese red panda (Ailurus fulgens styani) transported by airplane from Florida to a North Dakota zoo died 1 week after arrival. Grossly, an interscapular abscess, subcutaneous inflammation, lymphadenitis, and pulmonary abscesses were observed. Microscopic findings included necrotizing inflammation in liver, lung, lymph node, and spleen. Chromobacterium violaceum was cultured from the interscapular abscess, liver, lung, and spleen and was injected into Swiss Webster mice. These mice died 18 hours postinoculation, and C. violaceum was cultured from liver, lung, and spleen. Chromobacterium violaceum is a sporadically reported but highly virulent pathogenic bacterium of both animals and humans typically found as a soil and water inhabitant of tropical and subtropical regions.  (+info)

Intrinsic conformation of lipid A is responsible for agonistic and antagonistic activity. (6/183)

Lipopolysaccharides (LPS, endotoxin) represent a major virulence factor of Gram-negative bacteria, which can cause septic shock in mammals, including man. The lipid anchor of LPS to the bacterial outer membrane, lipid A, exhibits a peculiar chemical structure, harbours the 'endotoxic principle' of LPS and is also responsible for the expression of pathophysiological effects. Chemically modified lipid A can be endotoxically inactive, but may express strong antagonistic activity against endotoxically active LPS. By applying orientation measurements with attenuated total reflectance (ATR) infrared spectroscopy on hydrated lipid A samples, we show here that these different biological activities are directly correlated to the intrinsic conformation of lipid A. Bisphosphoryl-hexaacyl lipid A molecules with an asymmetric (4/2) distribution of the acyl chains linked to the diglucosamine backbone have a large tilt angle (> 45 degrees ) of the diglucosamine backbone with respect to the membrane surface, a conical molecular shape (larger cross-section of the hydrophobic than the hydrophilic moiety), and are endotoxically highly active. Monophosphoryl hexaacyl lipid A has a smaller tilt angle, and the conical shape is less expressed in favour of a more cylindrical shape. This correlates with decreasing endotoxic activity. Penta- and tetraacyl lipid A or hexaacyl lipid A with a symmetric acyl chain distribution (3/3) have a small tilt angle (< 25 degrees ) and a cylindrical shape and are endotoxically inactive, but may be antagonistic.  (+info)

Chromobacterium violaceum infection in Brazil. A case report. (7/183)

We report the second case of infection with Chromobacterium violaceum that occurred in Brazil. A farm worker living in the State of Sao Paulo presented fever and severe abdominal pain for four days. At hospitalization the patient was in a toxemic state and had a distended and painful abdomen. Chest X-ray and abdominal ultrasound revealed bilateral pneumonia and hypoechoic areas in the liver. The patient developed failure of multiple organs and died a few hours later. Blood culture led to isolation of C. violaceum resistant to ampicillin and cephalosporins and sensitive to chloramphenicol, tetracyclin, aminoglicosydes, and ciprofloxacin. Autopsy revealed pulmonary microabscesses and multiple abscesses in the liver. The major features of this case are generally observed in infections by C. violaceum: rapid clinical course, multiple visceral abscesses, and high mortality. Because of the antimicrobial resistance profile of this Gram-negative bacillus, for appropriate empirical antibiotic therapy it is important to consider chromobacteriosis in the differential diagnosis of severe community infections in Brazil.  (+info)

Plants secrete substances that mimic bacterial N-acyl homoserine lactone signal activities and affect population density-dependent behaviors in associated bacteria. (8/183)

In gram-negative bacteria, many important changes in gene expression and behavior are regulated in a population density-dependent fashion by N-acyl homoserine lactone (AHL) signal molecules. Exudates from pea (Pisum sativum) seedlings were found to contain several separable activities that mimicked AHL signals in well-characterized bacterial reporter strains, stimulating AHL-regulated behaviors in some strains while inhibiting such behaviors in others. The chemical nature of the active mimic compounds is currently unknown, but all extracted differently into organic solvents than common bacterial AHLs. Various species of higher plants in addition to pea were found to secrete AHL mimic activities. The AHL signal-mimic compounds could prove to be important in determining the outcome of interactions between higher plants and a diversity of pathogenic, symbiotic, and saprophytic bacteria.  (+info)

  • Chromobacterium violaceum sepsis in an infant. (
  • In general, Chromobacterium violaceum is involved in causing fatal cases of sepsis, visceral abscesses, and skin and soft tissue infections with mortality rate up to 65-80% [ 3 , 6 ]. (
  • Chromobacterium violaceum is a ß-proteobacterium found widely worldwide with important biotechnological properties and is associated to lethal sepsis in immune-depressed individuals. (
  • Se presentan 2 casos en niños el primero es un varón de 8 años con lesiones en piel , fiebre y adenitis inguinal, que ingresó con un cuadro de sepsis severa, síndrome de distrés respiratorio agudo (SDRA) y falleció a las 3 h del ingreso. (
  • El segundo caso, es una niña de 12 años con antecedente de fiebre y adenopatía inguinal secundaria a herida cortopunzante en el pie homolateral, que ingresó con un cuadro de sepsis , con desarrollo de abscesos múltiples profundos. (
  • Chromobacterium violaceum is a facultative anaerobic Gramnegative bacillus , widely distributed in water and soil in tropical and subtropical regions and associated with respiratory and gastrointestinal infections , liver abscesses , meningitis , endocarditis , hemophagocytic syndrome , and fulminant sepsis . (
  • Appendix 1 ) and assessed antimicrobial susceptibility patterns of Chromobacterium isolates ( Appendix 1 Table). (
  • We describe a case of Chromobacterium -associated pneumonia due to near-drowning and environmental investigation of a river site of the near-drowning. (
  • In this work, we identified pathways for production and uptake of siderophores, and we defined the role of these molecules in virulence of the bacterium Chromobacterium violaceum, an abundant component of the microbiota of soil and water, which occasionally causes serious infections in humans. (