| kinetic analysis of bacterial bioluminescence in water-organic media. | the interaction of luciferases from two types of luminous bacteria, photobacterium leiognathi and vibrio harveyi, with their substrates [the photorecovered fmnh2 and long-chain aldehydes--decanal (c10), dodecanal (c12) and tetradecanal (c14)] in water-organic media was analysed using kinetic graphical methods. moderate concentrations of organic solvents have been demonstrated to activate the bioluminescence, while higher concentrations inhibit it. the interactions of these effectors with lucifer ... | 2001 | 11512142 |
| the sos-lux-lac-fluoro-toxicity-test on the international space station (iss). | in the 21st century, an increasing number of astronauts will visit the international space station (iss) for prolonged times. therefore it is of utmost importance to provide necessary basic knowledge concerning risks to their health and their ability to work on the station and during extravehicular activities (eva) in free space. it is the aim of one experiment of the german project triple-lux (to be flown on the iss) to provide an estimation of health risk resulting from exposure of the astrona ... | 2003 | 12971406 |
| active-site copper and zinc ions modulate the quaternary structure of prokaryotic cu,zn superoxide dismutase. | the influence of the constitutive metal ions on the equilibrium properties of dimeric photobacterium leiognathi cu,zn superoxide dismutase has been studied for the wild-type and for two mutant protein forms bearing a negative charge in the amino acid clusters at the dimer association interface. depletion of copper and zinc dissociates the two mutant proteins into monomers, which reassemble toward the dimeric state upon addition of stoichiometric amounts of zinc. pressure-dependent dissociation i ... | 2003 | 12595249 |
| dominance of vibrio fischeri in secreted mucus outside the light organ of euprymna scolopes: the first site of symbiont specificity. | previous studies of the euprymna scolopes-vibrio fischeri symbiosis have demonstrated that, during colonization, the hatchling host secretes mucus in which gram-negative environmental bacteria amass in dense aggregations outside the sites of infection. in this study, experiments with green fluorescent protein-labeled symbiotic and nonsymbiotic species of gram-negative bacteria were used to characterize the behavior of cells in the aggregates. when hatchling animals were exposed to 10(3) to 10(6) ... | 2003 | 12839763 |
| characterization of the spectroscopic properties of the cu,co cluster in a prokaryotic superoxide dismutase. | a cu,co derivative of the cu,znsod from photobacterium leiognathi, in which cobalt has been selectively substituted for zinc, has been prepared and spectroscopically investigated. the derivative shows three bands in the visible region at 530, 566, and 600 nm when copper is in the oxidized state. reduction or depletion of the copper ion produce a shift of the band absorbing at 600 to 590 nm because of the detachment from copper of the imidazolate bridging the two metals when copper is in the oxid ... | 1999 | 10334865 |
| experimental and simulative dissociation of dimeric cu,zn superoxide dismutase doubly mutated at the intersubunit surface. | the equilibrium properties of dimeric photobacterium leiognathi cu,zn superoxide dismutase mutant bearing two negative charges in the amino acid clusters at the association interface has been studied, experimentally and computationally, and compared to those of the native enzyme. pressure-dependent dissociation is observed for the mutant, as observed by the fluorescence shift of the unique tryptophan residue located at the intersubunit surface. the spectral shift occurs slowly, reaching a platea ... | 2005 | 15681652 |
| collaborative effects of photobacterium cuzn superoxide dismutase (sods) and human ap endonuclease in dna repair and sod-deficient escherichia coli under oxidative stress. | the defenses against free radical damage include specialized repair enzymes that correct oxidative damage in dna and detoxification systems such as superoxide dismutases (sods). these defenses may be coordinated genetically as global responses. we hypothesized that the expression of sod and dna repair genes would inhibit dna damage under oxidative stress. therefore, protection of escherichia coli mutants deficient in sod and dna repair genes (sod-, xth-, and nfo-) was demonstrated by transformin ... | 2004 | 14744629 |
| genomic polymorphism in symbiotic populations of photobacterium leiognathi. | photobacterium leiognathi forms a bioluminescent symbiosis with leiognathid fishes, colonizing the internal light organ of the fish and providing its host with light used in bioluminescence displays. strains symbiotic with different species of the fish exhibit substantial phenotypic differences in symbiosis and in culture, including differences in 2-d page protein patterns and profiles of indigenous plasmids. to determine if such differences might reflect a genetically based symbiont-strain/host ... | 2004 | 14756879 |
| dynamic features of the subunit interface of cu,zn superoxide dismutase as probed by tryptophan phosphorescence. | as part of the more general inquiry on the molecular basis of specific recognition between macromolecules, the subunit-subunit interface structure of dimeric superoxide dismutase from photobacterium leiognathi has been probed selectively by the phosphorescence emission of trp-73, located at the subunit contact region. copper at the catalytic site was found to quench completely the delayed emission and therefore all studies were conducted with the copper-free or cd(2+)-substituted protein. the sp ... | 2001 | 11414691 |
| riboflavin synthesis genes ribe, ribb, ribh, riba reside in the lux operon of photobacterium leiognathi. | nucleotide sequence of the riboflavin synthesis genes ribe, ribb, ribh, riba (genbank accession no. af364106) resided in the lux operon of photobacterium leiognathi pl741 has been determined, and the amino acid sequences of riboflavin synthetase (ribe), dhbp synthetase (ribb), lumazine synthetase (ribh), gtp cyclohydrolase ii (riba) encoded by the riboflavin synthesis genes are deduced. nucleotide sequence reveals that the ribe gene encodes the riboflavin synthetase responsible for converting lu ... | 2001 | 11396941 |
| [effect of glucose on luciferase expression in photobacterium leiognathi]. | photobacterium leiognathi cultured in marine broth emits a luminescence that is temporarily enhanced and then extinguished by glucose. glucose reduces the luciferase level and the expression of lux abg mrna in p. leiognathi. the amount of atp in p. leiognathi is temporarily increased and then declines to the normal level. these results indicate that the extinguishing by glucose in p. leiognathi is induced by the interruption of the translation of luciferase. | 2004 | 15467278 |
| single mutations at the subunit interface modulate copper reactivity in photobacterium leiognathi cu,zn superoxide dismutase. | the functional properties and x-ray structures of five mutant forms of photobacterium leiognathi cu,zn superoxide dismutase carrying single mutations at residues located at the dimer association interface have been investigated. when compared to the wild-type enzyme, the three-dimensional structures of the mutants show structural perturbations limited to the proximity of the mutation sites and substantial identity of active site geometry. nonetheless, the catalytic rates of all mutants, measured ... | 2001 | 11327787 |
| vibrios of the spotted rose snapper lutjanus guttatus steindachner, 1869 from northwestern mexico. | to characterize and identify vibrios present in wild and cultured juvenile snappers (lutjanus guttatus) in northwestern mexico. | 2007 | 17578416 |
| interaction of aromatic compounds with photobacterium leiognathi luciferase: fluorescence anisotropy study. | the time-resolved and steady-state fluorescence techniques were employed to elucidate possible interactions of four aromatic compounds (anthracene, popop, msb and 1,4-naphthalendiol) with bacterial luciferase. fluorescence spectra and fluorescence anisotropy decays of these compounds were studied in ethanol, water-ethanol solutions and in the presence of bacterial luciferase. shifts of fluorescent spectra and differences in rotational correlation times are interpreted in terms of weak (hydrophob ... | 2003 | 12701091 |
| characteristic analysis of the luxg gene encoding the probable flavin reductase that resides in the lux operon of photobacterium leiognathi. | nucleotide sequence of the luxg gene (genbank accession no. af053227) from photobacterium leiognathi pl741 has been determined, and the encoded probable flavin reductase is deduced. the probable flavin reductase encoded by the luxg gene has a calculated m(r) 26,544 and comprises 235 amino acid residues. the probable flavin reductase like the nad(p)h-flavin reductase might catalyze the reduction of flavins. alignment and comparison of the probable flavin reductases from p. leiognathi pl741, atcc ... | 1998 | 9610381 |
| a novel and sensitive test for rapid determination of water toxicity. | the performance of a novel, rapid, and sensitive test for detecting chemical toxicants in water is described in this article. the bioassay utilizes a highly sensitive variant of the luminescent bacterium photobacterium leiognathi that allows the detection in water at levels below milligrams per liter of diverse groups of toxicants, including heavy metals, pesticides, pcbs, polycyclic aromatic hydrocarbons, and fuel traces. for most toxic agents reported in this study, the new assay was markedly ... | 2002 | 12112638 |
| distribution and identification of luminous bacteria from the sargasso sea. | vibrio fischeri and lucibacterium harveyi constituted 75 of the 83 luminous bacteria isolated from sargasso sea surface waters. photobacterium leiognathi and photobacterium phosphoreum constituted the remainder of the isolates. luminescent bacteria were recovered at concentrations of 1 to 63 cells per 100 ml from water samples collected at depths of 160 to 320 m. two water samples collected at the thermocline yielded larger numbers of viable, aerobic heterotrophic and luminous bacteria. luminesc ... | 1980 | 16345575 |
| identification of vibrio splendidus as a member of the planktonic luminous bacteria from the persian gulf and kuwait region with luxa probes. | hybridization probes specific for the luxa genes of four groups of luminous bacteria were used to screen luminous isolates obtained from the persian gulf, near al khiran, kuwait nine of these isolates were identified as vibrio harveyi, a commonly encountered planktonic isolate, while three others showed no hybridization to any of the four probes (v. harveyi, vibrio fischeri, photobacterium phosphoreum, or photobacterium leiognathi) under high-stringency conditions. polymerase chain reaction ampl ... | 1993 | 16349023 |
| phenotypic characterization of the marine pathogen photobacterium damselae subsp. piscicida. | the taxonomic position of photobacterium damselae subsp. piscicida, the causative agent of fish pasteurellosis, is controversial as this organism has also been described as 'pasteurella piscicida'. to clarify the taxonomic position of the pathogen, a total of 113 p. damselae subsp. piscicida strains and 20 p. damselae subsp. damselae strains, isolated from different geographical areas and from the main affected fish species, were analysed using 129 morphological and biochemical tests, including ... | 1998 | 9828416 |
| seasonal and geographic distribution of luminous bacteria in the eastern mediterranean sea and the gulf of elat. | luminous bacteria in the mediterranean sea and the gulf of aqaba-elat have different distribution patterns. in the mediterranean sea, beneckea harveyi is present all year round, with different subtypes alternating in summer and winter; photobacterium fischeri was only present during the winter. in the gulf of elat, p. leiognathi is present throughout the water column in similar densities during the entire year. this constancy in distribution is presumably due to the near-constancy in water tempe ... | 1979 | 16345404 |
| static and dynamic water molecules in cu,zn superoxide dismutase. | understanding protein hydration is a crucial, and often underestimated issue, in unraveling protein function. molecular dynamics (md) computer simulation can provide a microscopic description of the water behavior. we have applied such a simulative approach to dimeric photobacterium leiognathi cu,zn superoxide dismutase, comparing the water molecule sites determined using 1.0 ns md simulation with those detected by x-ray crystallography. of the water molecules detected by the two techniques, 20% ... | 2003 | 12784219 |
| luxa gene of light organ symbionts of the bioluminescent fish acropoma japonicum (acropomatidae) and siphamia versicolor (apogonidae) forms a lineage closely related to that of photobacterium leiognathi ssp. mandapamensis. | a molecular phylogenetic analysis of luxa gene sequences of light organ symbionts of the fish acropoma japonicum (acropomatidae) and siphamia versicolor (apogonidae) revealed that the sequences were related to those of photobacterium leiognathi ssp. mandapamensis, which is not known to occur as a light organ symbiont among bioluminescent p. leiognathi clades. the presence of another lux gene element, luxf, coding for nonfluorescent protein, provided additional support for the identity of the lig ... | 2006 | 16842343 |
| [heterogeneity of the populations of marine luminescent bacteria photobacterium leiognathi under different conditions of cultivation]. | manifestation of pleiotropic effects in the isogenic variants of luminescent bacteria photobacterium leiognathi 54 was investigated. the decrease or increase of the expression level of bioluminescence was caused by changes in lux operon regulation. the dynamics of the bioluminescence of dark and dim variants did not differ from the dynamics of the initial luminescent variant, but dependence of the level of luminescence intensity on the exogenous autoinductor of the lux operon was revealed. the i ... | 2006 | 16871801 |
| phylogenetic analysis of the lux operon distinguishes two evolutionarily distinct clades of photobacterium leiognathi. | the luminous marine bacterium photobacterium mandapamensis was synonymized several years ago with photobacterium leiognathi based on a high degree of phenotypic and genetic similarity. to test the possibility that p. leiognathi as now formulated, however, actually contains two distinct bacterial groups reflecting the earlier identification of p. mandapamensis and p. leiognathi as separate species, we compared p. leiognathi strains isolated from light-organ symbiosis with leiognathid fishes (i.e. ... | 2004 | 15034641 |
| stability of chloramphenicol residues in shrimp subjected to heat processing treatments. | the stability of chloramphenicol residues in white shrimp (penaeus indicus) subjected to cooking (100 degrees c) for 10, 20 and 30 min (c1, c2 and c3) as well as retorting (121 degrees c) for 10 and 15 min (r1 and r2) was studied by a microbial assay method using photobacterium leiognathi as the test organism. the microbial assay method was found to have a good sensitivity of 1 microg/ml the loss of chloramphenicol in shrimp subjected to cooking for 10, 20 and 30 min was 6%, 12% and 29%, respect ... | 2006 | 16942985 |
| effect of heavy atoms in bioluminescent reactions. | bioluminescent reactions of luminous organisms are excellent models for studying the effects of heavy atoms on enzymatic processes. the effects of potassium halides with halide anions of different atomic weight were compared in bioluminescent reactions of the firefly (luciola mingrelica), a marine coelenterate (obelia longissima), and a marine bacterium (photobacterium leiognathi). two mechanisms of the effects of the halides were examined-the physicochemical effect of the external heavy atom, b ... | 2007 | 17237922 |
| bioluminescence and exogenous compounds: physico-chemical basis for bioluminescent assay. | bioluminescent systems are convenient objects to study mechanisms of influence of exogenous molecules on living organisms. classification of physical and physico-chemical mechanisms of the effects of luminous bacteria photobacterium leiognathi on bioluminescent reactions is suggested. five mechanisms are discussed: (1) change of electron-excited states' population and energy transfer, (2) change of efficiency of s-t conversion in the presence of external heavy atom, (3) change of rates of couple ... | 2006 | 16413195 |
| the sos-lux-toxicity-test on the international space station. | for the safety of astronauts and to ensure the stability and integrity of the genome of microorganisms and plants used in bioregenerative life support systems, it is important to improve our knowledge of the combined action of (space) radiation and microgravity. the sos-lux-toxicity test, as part of the triple-lux project (accepted for flight at biolab in columbus on the international space station, (iss)), will provide an estimation of the health risk resulting from exposure of astronauts to th ... | 2006 | 16431084 |
| photobacterium rosenbergii sp. nov. and enterovibrio coralii sp. nov., vibrios associated with coral bleaching. | six new vibrio-like isolates originating from different species of bleached and healthy corals around magnetic island (australia) were investigated using a polyphasic approach. phylogenetic analyses based on 16s rrna, reca and rpoa gene sequences split the isolates in two new groups. strains lmg 22223(t), lmg 22224, lmg 22225, lmg 22226 and lmg 22227 were phylogenetic neighbours of photobacterium leiognathi lmg 4228(t) (95.6 % 16s rrna gene sequence similarity), whereas strain lmg 22228(t) was r ... | 2005 | 15774685 |
| characterization of fe/mn-superoxide dismutase from diatom thallassiosira weissflogii: cloning, expression, and property. | a cdna clone of 1114 bp encoding a putative mn-superoxide dismutase (mn-sod) from diatom thallassiosira weissflogii was cloned by the pcr technique. nucleotide sequence analysis of this cdna clone revealed that it was translated into 201 amino acid residues. when the sequence was compared with mn-sods from vibrio mimicus and escherichia coli, as well as two fe-sods from e. coli and photobacterium leiognathi, this sod showed higher homology to mn-sod. the amino acid residues required to coordinat ... | 2005 | 15740026 |
| phylogenetic diversity and cosymbiosis in the bioluminescent symbioses of "photobacterium mandapamensis". | "photobacterium mandapamensis" (proposed name) and photobacterium leiognathi are closely related, phenotypically similar marine bacteria that form bioluminescent symbioses with marine animals. despite their similarity, however, these bacteria can be distinguished phylogenetically by sequence divergence of their luminescence genes, luxcdab(f)e, by the presence (p. mandapamensis) or the absence (p. leiognathi) of luxf and, as shown here, by the sequence divergence of genes involved in the synthesi ... | 2007 | 17369329 |
| on-line determination of serum bactericidal activity using recombinant luminescent bacteria. | intensity of luminescence quenching in recombinant strains of escherichia coli with cloned lux-operones by human blood serum is directly proportional to the degree of bactericidal effect assessed by nephelometric and bacteriological methods. this correlation was most characteristic of e. coli with luminescence genes from photobacterium leiognathi, which substantiates its use in the development of the kinetic bioluminescent method to determine of serum bactericidal activity. the possibility of us ... | 2006 | 17369948 |
| [conditions that influence bacterial luminescence in the presence of blood serum]. | conditions that influence the luminescence of natural and recombinant luminescent bacteria in the presence of blood serum were studied. in general, blood serum quenched the luminescence of the marine photobacterium phosphoreum and the recombinant escherichia coli strains harboring the luminescent system genes of photobacterium leiognathi, but enhanced the luminescence of the soil bacterium photorhabdus luminescens zm1 and the recombinant e. coli strain harboring the lux operon of p. luminescens ... | 2005 | 15938395 |
| bioluminescence-mediated stimulation of photoreactivation in bacteria. | although biochemistry and genetics of light emission by cells have been investigated in detail, a biological role for bacterial luminescence has remained obscure for a long time. it was proposed recently that luminescence may stimulate dna repair, but the specific mechanism of this phenomenon was not investigated. moreover, experiments showing decreased survival of uv-irradiated lux mutants relative to luminescent cells were performed previously using only one bacterial species, vibrio harveyi. ... | 2005 | 16040205 |
| biochemical characterization of a cambialistic superoxide dismutase isozyme from diatom thallassiosira weissflogii: cloning, expression, and enzyme stability. | a cdna clone of 1081 bp encoding a second putative superoxide dismutase (sod) from diatom thallassiosira weissflogii was cloned by the polymerase chain reaction technique. the cdna encodes a protein of 286 amino acid residues. alignment of the truncated sod sequence containing 217 amino acid residues with mn-sods from vibrio mimicus and escherichia coli, as well as two fe-sods from e. coli and photobacterium leiognathi, this sod showed greater homology to mn-sod. the residues required to coordin ... | 2005 | 16076113 |
| random isotopolog libraries for protein perturbation studies. 13c nmr studies on lumazine protein of photobacterium leiognathi. | [graph: see text] lumazine proteins of luminescent bacteria are paralogs of riboflavin synthase which are devoid of catalytic activity but bind the riboflavin synthase substrate, 6,7-dimethyl-8-ribityllumazine, with high affinity and are believed to serve as optical transponders for bioluminescence emission. lumazine protein of photobacterium leiognathi was expressed in a recombinant escherichia coli host and was reconstituted with mixtures (random libraries) of 13c-labeled isotopologs of 6,7-di ... | 2005 | 16292826 |
| luxg is a functioning flavin reductase for bacterial luminescence. | the luxg gene is part of the lux operon of marine luminous bacteria. luxg has been proposed to be a flavin reductase that supplies reduced flavin mononucleotide (fmn) for bacterial luminescence. however, this role has never been established because the gene product has not been successfully expressed and characterized. in this study, luxg from photobacterium leiognathi th1 was cloned and expressed in escherichia coli in both native and c-terminal his6-tagged forms. sequence analysis indicates th ... | 2008 | 18156264 |
| the dimeric assembly of photobacterium leiognathi and salmonella typhimurium sodc1 cu,zn superoxide dismutases is affected differently by active site demetallation and ph: an analytical ultracentrifuge study. | to establish whether the species-specific variations at the subunit interface of bacterial cu,zn superoxide dismutases affect dimer assembly, the association state of the photobacterium leiognathi (plsod) and salmonella typhimurium (stsod) enzymes, which differ in 11 out of 19 interface residues, was investigated by analytical ultracentrifugation. the same linkage pattern correlates quaternary assembly, active site metallation, and ph in the two enzymes albeit with quantitative differences. both ... | 2008 | 18179768 |
| sensitivity of dark mutants of various strains of luminescent bacteria to reactive oxygen species. | recent studies indicated that bioluminescence of the marine bacterium vibrio harveyi may both stimulate dna repair and contribute to detoxification of deleterious oxygen derivatives. therefore, it was also proposed that these reactions can be considered biological roles of bacterial luminescence and might act as evolutionary drives in development of luminous systems. however, experimental evidence for the physiological role of luciferase in protection of cells against oxidative stress has been d ... | 2005 | 15717160 |
| isolation and characterization of marine luminous bacteria from shallow coastal waters of taiwan. | marine luminous bacteria were isolated and identified from samples in shallow coastal waters of taiwan during the relatively warm seasons. | 2007 | 17332902 |
| immobilization as a technical possibility for long-term storage of bacterial biosensors. | for applications in field experiments, the recombinant strain salmonella typhimurium ta1535 was immobilized to permit its immediate utilization after long storage periods. salmonella typhimurium ta1535 cells contain the plasmid that has an inducible sos promoter fused to a promoterless luxcdabfe operon from photobacterium leiognathi. the induction of bioluminescence occurs in the presence of the dna-damaging agent mitomycin c which stimulates the bacterial sos response. early stationary phase ce ... | 2005 | 15791471 |
| developmental and microbiological analysis of the inception of bioluminescent symbiosis in the marine fish nuchequula nuchalis (perciformes: leiognathidae). | many marine fish harbor luminous bacteria as bioluminescent symbionts. despite the diversity, abundance, and ecological importance of these fish and their apparent dependence on luminous bacteria for survival and reproduction, little is known about developmental and microbiological events surrounding the inception of their symbioses. to gain insight on these issues, we examined wild-caught larvae of the leiognathid fish nuchequula nuchalis, a species that harbors photobacterium leiognathi as its ... | 2008 | 18978090 |
| effect of quinone on the fluorescence decay dynamics of endogenous flavin bound to bacterial luciferase. | the interaction of quinone with luciferase from photobacterium leiognathi was studied based on the fluorescence decay measurements of the endogenous flavin bound to the enzyme. homologous 1,4-quinones, 1,4-benzoquinone, methyl-1,4-benzoquinone, 2-methyl-5-isopropyl-1,4-benzoquine and 1,4-naphthoquinone, were investigated. in the absence of quinone, the fluorescence intensity and anisotropy decays of the endogenous flavin exhibited two intensity decay lifetimes (~1 and 5 ns) and two anisotropy de ... | 2009 | 19162392 |
| an alpha2,6-sialyltransferase cloned from photobacterium leiognathi strain jt-shiz-119 shows both sialyltransferase and neuraminidase activity. | we cloned, expressed, and characterized a novel beta-galactoside alpha2,6-sialyltransferase from photobacterium leiognathi strain jt-shiz-119. the protein showed 56-96% identity to the marine bacterial alpha2,6-sialyltransferases classified into glycosyltransferase family 80. the sialyltransferase activity of the n-terminal truncated form of the recombinant enzyme was 1477 u/l of escherichia coli culture. the truncated recombinant enzyme was purified as a single band by sodium dodecyl sulfate po ... | 2010 | 19797322 |
| synthesis, cytotoxicity by bioluminescence inhibition, antibacterial and antifungal activity of ([1,2,4]triazolo[1,5-c]quinazolin-2-ylthio)carboxylic acid amides. | we report in this work the synthesis, cytotoxicity, and antimicrobial activity of ([1,2,4]triazolo[1,5-c]quinazolin-2-ylthio)carboxylic acid amides 4-7 in connection with our previous research in the preparation of triazoloquinazoline derivatives. due to simplicity, general availability of starting materials, and high yields, the most reliable method of synthesis appeared to be the one with n,n-carbonyldiimidazole activation stage. the chemical structures of all obtained substances were deduced ... | 2009 | 19882690 |
| [quantitative detection of nadh by in vitro bacterial luciferase bioluminescent]. | the study aimed at establishing the bacterial luciferase: fmn-nadh oxidoreductase bioluminescent system in vitro and evaluating its potential for quantitative detection of nadh. | 2009 | 20030062 |
| phylogenetic analysis of the incidence of lux gene horizontal transfer in vibrionaceae. | horizontal gene transfer (hgt) is thought to occur frequently in bacteria in nature and to play an important role in bacterial evolution, contributing to the formation of new species. to gain insight into the frequency of hgt in vibrionaceae and its possible impact on speciation, we assessed the incidence of interspecies transfer of the lux genes (luxcdabeg), which encode proteins involved in luminescence, a distinctive phenotype. three hundred three luminous strains, most of which were recently ... | 2008 | 18359809 |
| phylogeny, genomics, and symbiosis of photobacterium. | photobacterium comprises several species in vibrionaceae, a large family of gram-negative, facultatively aerobic, bacteria that commonly associate with marine animals. members of the genus are widely distributed in the marine environment and occur in seawater, surfaces, and intestines of marine animals, marine sediments and saline lake water, and light organs of fish. seven photobacterium species are luminous via the activity of the lux genes, luxcdabeg. much recent progress has been made on the ... | 2010 | 20883503 |
| a cmp-n-acetylneuraminic acid synthetase purified from a marine bacterium, photobacterium leiognathi jt-shiz-145. | a cytidine 5'-monophospho-n-acetylneuraminic acid (cmp-neu5ac) synthetase was found in a crude extract prepared from photobacterium leiognathi jt-shiz-145, a marine bacterium that also produces a ß-galactoside a2,6-sialyltransferase. the cmp-neu5ac synthetase was purified from the crude extract of the cells by a combination of anion-exchange and gel filtration column chromatography. the purified enzyme migrated as a single band (60 kda) on sodium dodecylsulfate-polyacrylamide gel electrophoresis ... | 2011 | 21228490 |
| [synthesis of reserve polyhydroxyalkanoates by luminescent bacteria]. | the ability of marine luminescent bacteria to synthesize polyesters of hydroxycarboxylic acids (polyhydroxyalkanoates, pha) as reserve macromolecules was studied. twenty strains from the collection of the luminescent bacteria ccibso (wdsm839) of the institute of biophysics, siberian branch, russian academy of sciences, assigned to different taxa (photobacterium leiognathi, ph. phosphoreum, vibrio harveyi, and v. fischeri) were analyzed. the most productive strains were identified, and the condit ... | 2008 | 18683654 |
| structure of lumazine protein, an optical transponder of luminescent bacteria. | the intensely fluorescent lumazine protein is believed to be involved in the bioluminescence of certain marine bacteria. the sequence of the catalytically inactive protein resembles that of the enzyme riboflavin synthase. its non-covalently bound fluorophore, 6,7-dimethyl-8-ribityllumazine, is the substrate of this enzyme and also the committed precursor of vitamin b(2). an extensive crystallization screen was performed using numerous single-site mutants of the lumazine protein from photobacteri ... | 2008 | 18602927 |
| effect of halogenated fluorescent compounds on bioluminescent reactions. | the paper investigates an application of luminescent bioassays to monitor the toxicity of organic halides. effects of xanthene dyes (fluorescein, eosin y, and erythrosin b), used as model compounds, on bioluminescent reactions of firefly luciola mingrelica, marine bacteria photobacterium leiognathi, and hydroid polyp obelia longissima were studied. dependence of bioluminescence quenching constants on the atomic weight of halogen substituents in dye molecules was demonstrated. bacterial biolumine ... | 2011 | 21336798 |
| photobacterium jeanii sp. nov., isolated from corals and zoanthids. | four novel isolates (r-40508(t), r-40507, r-40903 and r-21419) were obtained from different cnidarian species (phyllogorgia dilatata, merulina ampliata and palythoa caribaeorum) from different places in brazil and australia. the novel isolates formed a tight phylogenetic group based on 16s rrna, reca, topa, ftsz, mreb and rpoa gene sequences. their closest phylogenetic neighbours were the type strains of photobacterium leiognathi, p. rosenbergii and p. halotolerans, sharing 97.1-97.5 % 16s rrna ... | 2010 | 20081016 |
| natural merodiploidy of the lux-rib operon of photobacterium leiognathi from coastal waters of honshu, japan. | sequence analysis of the bacterial luminescence (lux) genes has proven effective in helping resolve evolutionary relationships among luminous bacteria. phylogenetic analysis using lux genes, however, is based on the assumptions that the lux genes are present as single copies on the bacterial chromosome and are vertically inherited. we report here that certain strains of photobacterium leiognathi carry multiple phylogenetically distinct copies of the entire operon that codes for luminescence and ... | 2007 | 17586644 |
| synthesis and biological activity of novel n-cycloalkyl-(cycloalkylaryl)-2-[(3-r-2-oxo-2h-[1,2,4]triazino[2,3-c]quinazoline-6-yl)thio]acetamides. | in this paper the novel n-cycloalkyl-(cycloalkylaryl)-2-[(3-r-2-oxo-2h-[1,2,4]triazino[2,3-c]quinazoline-6-yl)thio]acetamides synthesis by aminolysis of activated by thionyl chloride or carbonyldiimidazole [(3-r-2-oxo-2h-[1,2,4]triazino[2,3-c]quinazolin-6-yl)-thio]acetic acids and alkylation of the 3-r-6-thio-6,7-dihydro-2h-[1,2,4]triazino[2,3-c]quinazoline-2-ones potassium salts with n-cycloalkyl-(cycloalkylaryl)-2-chloroacetamides are proposed. the structures of compounds are determined by (1) ... | 2011 | 22051065 |
| lumazine proteins from photobacteria: localization of the single ligand binding site to the n-terminal domain. | lumazine protein is believed to serve as an optical transponder in bioluminescence emission by certain marine bacteria. sequence arguments suggest that the protein comprises two similarly folded riboflavin synthase-type domains, but earlier work also suggested that only one domain binds 6,7-dimethyl-8-ribityllumazine (dmrl). we show that the replacement of serine-48 or threonine-50 in the n-terminal domain of lumazine protein of photobacterium leiognathi modulates the absorbance and fluorescence ... | 2007 | 18020947 |
| design and evaluation of novel antimicrobial and anticancer agents among tetrazolo[1,5-c]quinazoline-5-thione s-derivatives. | the novel heterocyclization of 5-(2-aminophenyl)-1h-tetrazole with potassium ethylxanthogenate or carbon disulfide was proposed. the potassium salt of the tetrazolo[1,5-c]quinazoline-5-thione was subsequently modified by alkylation with proper halogen derivatives to (tetrazolo[1,5-c]quinazolin-5-ylthio)alkyls, n,n-dialkylethylamines, 1-aryl-2-ethanones, 1-(alkyl)aryl-2-ethanols, carboxylic acids, and esters. the structures of all newly synthesized compounds were confirmed by ft-ir, uv-vis, lc-ms ... | 2012 | 23641327 |
| differential analysis of bactericidal systems of blood serum with recombinant luminescent escherichia coli and bacillus subtilis strains. | luminescence intensity of recombinant escherichia coli and bacillus subtilis strains with cloned luxcd(ab)e genes of the natural luminescent microorganism photobacterium leiognathi was studied under the influence of 30 individual samples of human blood serum of different component composition. a relationship was found between the level of residual bioluminescence and degree of the bactericidal effect. moreover, the inhibition of e. coli lux+ luminescence was shown to be related to activity of th ... | 2012 | 23330091 |
| substituted 2-[(2-oxo-2h-[1,2,4]triazino [2,3-c]quinazolin-6-yl)thio]acetamides with thiazole and thiadiazole fragments: synthesis, physicochemical properties, cytotoxicity, and anticancer activity. | the series of novel n-r-2-[(3-r-2-oxo-2h-[1,2,4]triazino[2,3-c]quinazolin-6-yl)thio]acetamides with thiazole and thiadiazole fragments in a molecule were obtained by alkylation of potassium salts 1.1-1.4 by n-hetaryl-2-chloroacetamides and by aminolysis of activated acids 2.1-2.4 with n,n'-carbonyldiimidazole (cdi). the structures of compounds were determined by ir, (1)h nmr, ms, and ei-ms analysis. the results of cytotoxicity evaluated by the bioluminescence inhibition of bacterium photobacteri ... | 2012 | 23264935 |
| antimicrobial effects of silver nanoparticles stabilized in solution by sodium alginate. | to investigate the effect of nanosilver particles in solution stabilized in a matrix of sodium alginate on the growth and development of pathogenic bacteria such as staphylococcus aureus, enterococcus faecalis, escherichia coli, proteus vulgaris, enterobacter cloacae, the antibiotic-resistant strain of pseudomonas aeruginosa, the yeast-like fungus candida albicans, and the luminescent bacteria photobacterium leiognathi sh1. | 2016 | 27747311 |
| facile synthesis of gold-silver alloy nanoparticles for application in metal enhanced bioluminescence. | in the present study we explored metal enhanced bioluminescence in luciferase enzymes for the first time. for this purpose a simple and reproducible one pot synthesis of gold-silver alloy nanoparticles was developed. by changing the molar ratio of tri-sodium citrate and silver nitrate we could synthesize spherical au-ag colloids of sizes ranging from 10 to 50 nm with a wide range of localized surface plasmon resonance (lspr) peaks (450-550 nm). the optical tunability of the au-ag colloids enable ... | 2014 | 24865663 |
| diversification of two lineages of symbiotic photobacterium. | understanding of processes driving bacterial speciation requires examination of closely related, recently diversified lineages. to gain an insight into diversification of bacteria, we conducted comparative genomic analysis of two lineages of bioluminescent symbionts, photobacterium leiognathi and 'p. mandapamensis'. the two lineages are evolutionary and ecologically closely related. based on the methods used in bacterial taxonomy for classification of new species (dna-dna hybridization and ani), ... | 2013 | 24349398 |
| characteristics of endogenous flavin fluorescence of photobacterium leiognathi luciferase and vibrio fischeri nad(p)h:fmn-oxidoreductase. | the bioluminescent bacterial enzyme system nad(p)h:fmn-oxidoreductase-luciferase has been used as a test system for ecological monitoring. one of the modes to quench bioluminescence is the interaction of xenobiotics with the enzymes, which inhibit their activity. the use of endogenous flavin fluorescence for investigation of the interactions of non-fluorescent compounds with the bacterial luciferase from photobacterium leiognathi and nad(p)h:fmn-oxidoreductase from vibrio fischeri has been propo ... | 2005 | 15924327 |
| expression, purification, and characterization of a recombinant flavin reductase from the luminescent marine bacterium photobacterium leiognathi: a set of exercises for students. | in photobacterium, the flavin reductase encoded by luxg regenerates the reduced form of flavin mononucleotide (fmn). reduced fmn is one of the substrates of the luciferase enzyme that catalyzes a light-emitting reaction. a set of experiments, that employs a luxg-expression plasmid construct (pghis) and is suitable for an undergraduate laboratory course, is presented. hexahistidine-tagged protein is expressed in e. coli from pghis, with the t7 rna polymerase/lac repressor induction system. bacter ... | 2010 | 21567817 |
| development of immobilized biophotonic beads consisting of photobacterium leiognathi for the detection of heavy metals and pesticide. | the present communication deals with construction of immobilized robust biophotonic bead using p. leiognathi, a marine luminescent bacterium for their possible application in monitoring of environmental toxicants. immobilization efficiency of agar, carrageenan and sodium alginate was evaluated separately in terms of luminescence response and was recorded as 30.3, 77.4 or 99.5%, respectively. under optimized storage conditions, the luminescent response of p. leiognathi in the immobilized state wa ... | 2012 | 22626628 |
| [trigger factor dependent refolding of bacterial luciferases in escherichia coli cells: kinetics, efficiency and effect of the bichaperone system, dnakje-clpb]. | here were determined the basic parameters of the tigger factor (tf) -dependent refolding of thermal inactivated bacterial luciferases. the tf-dependent refolding is less efficient and requires more time than dnakje-dependent refolding. the increase in the intracellular concentration of tf leads to an apparent decrease in the level of the thermal inactivated bacterial luciferase refolding. for thermolabile luciferases, the level of tf-dependent refolding is significantly higher, than for thermost ... | 2013 | 23888781 |
| 1-r-2-([1,2,4]triazolo[1,5-c]quinazoline-2-ylthio)etanon(ol)s: synthesis, bioluminescence inhibition, molecular docking studies, antibacterial and antifungal activities. | the increasing mortality due to antibacterial resistance necessitates the search for novel antimicrobial agents. hence, series of 1-r-2-([1,2,4]triazolo[1,5-c]quinazoline-2-ylthio)etanon(ol)s were synthesized, evaluated by spectral data and studied against st. aureus, m. luteum, e. faecalis, e. aerogenes, p. aeruginosa, c. sakazakii, e. coli, k. pneumonia, hospital streptococcus spp., c. albicans and a. niger in 100, 500 µg/ml and 100 µg/disk. substances exhibited moderate toxicity in 0.025, 0.1 ... | 2016 | 27012316 |
| 1-r-2-([1,2,4]triazolo[1,5-c]quinazoline-2-ylthio)etanon(ol)s: synthesis, bioluminescence inhibition, molecular docking studies, antibacterial and antifungal activity. | the increasing mortality due to antibacterial resistance necessitates the search for novel antimicrobial agents. hence, series of 1-r-2-([1,2,4]triazolo[1,5-c]quinazoline-2-ylthio)etanon(ol)s were synthesized, evaluated by spectral data and studied against st. aureus, m. luteum, e. faecalis, e. aerogenes, p. aeruginosa, c. sakazakii, e.coli, k. pneumonia, hospital streptococcus spp., c. albicans and a. niger in 100, 500 µg/ml and 100 µg/disk. substances exhibited moderate toxicity in 0.025, 0.1 ... | 2016 | 26813534 |
| [photoreactivation of uv-irradiated escherichia coli k12 ab1886 uvra6 with assistance of luminescence of photobacterium leiognathi luciferase]. | the bioluminescence induced by luciferases of marine bacteria promotes repair of uv damaged dna of escherichia coli ab1886 uvra6. it is shown that bacterial photolyase that implements photoreactivation activity is the major contributor to dna repair. however, the intensity of bioluminescence increasing induced by uv-irradiation (sos-induction) in bacterial cells is not enough for efficient photoreactivation. | 2015 | 26710787 |
| [photoreactivating activity of bioluminescence: repair of uv-damaged dna of escherichia coli occurs with assistance of lux-genes of marine bacteria]. | the uv resistance of luminescent bacteria escherichia coli ab1886 uvra6 (pleo1) containing the plasmid with luxcdabe genes of marine bacteria photobacterium leiognathi is approximately two times higher than the uv resistance of non-luminous bacteria e. coli ab1886 uvra6. introduction of phr::kan(r) mutations (a defect in the functional activity of photolyase) into the genome of e. coli ab1886 uvra6 (pleo1) completely removes the high uv resistance of the cells. therefore, photoreactivation that ... | 2015 | 26591600 |
| [glycosides of hydroxylamine derivatives. i. phase transfer synthesis and study of isatine-3-oximes glucosaminides influence on bacterial luminescence]. | in the phase transfer system solid calcium carbonate-acetonitrile, per acetate alpha-d-glucosaminilchloride glycosilate easily deprotoned isatine-3-oximes hydroxyl groups. it was found that the presence in the reaction mixture a catalytic amounts of 15-crown-5 accelerated the process twice. obtained o-beta-d-glucosaminides were identified with 1h-nmr spectroscopy. features of synthesized compound's nmr spectra are discussed in comparison with those of another n-acetylglucosamine 1-o-derivatives. ... | 2011 | 21721259 |
| genetically encoded sensors of protein hydrodynamics and molecular proximity. | the specialized light organ of the ponyfish supports the growth of the bioluminescent symbiont photobacterium leiognathi. the bioluminescence of p. leiognathi is generated within a heteromeric protein complex composed of the bacterial luciferase and a 20-kda lumazine binding protein (lump), which serves as a förster resonance energy transfer (fret) acceptor protein, emitting a cyan-colored fluorescence with an unusually long excited state lifetime of 13.6 ns. the long fluorescence lifetime and s ... | 2015 | 25931526 |
| trigger factor assists the refolding of heterodimeric but not monomeric luciferases. | the refolding of thermally inactivated protein by atp-independent trigger factor (tf) and atp-dependent dnakje chaperones was comparatively analyzed. heterodimeric (αβ) bacterial luciferases of aliivibrio fischeri, photobacterium leiognathi, and vibrio harveyi as well as monomeric luciferases of vibrio harveyi and luciola mingrelica (firefly) were used as substrates. in the presence of tf, thermally inactivated heterodimeric bacterial luciferases refold, while monomeric luciferases do not refold ... | 2014 | 24512665 |
| synthesis of α,β-unsaturated aldehydes as potential substrates for bacterial luciferases. | bacterial luciferase catalyzes the monooxygenation of long-chain aldehydes such as tetradecanal to the corresponding acid accompanied by light emission with a maximum at 490nm. in this study even numbered aldehydes with eight, ten, twelve and fourteen carbon atoms were compared with analogs having a double bond at the α,β-position. these α,β-unsaturated aldehydes were synthesized in three steps and were examined as potential substrates in vitro. the luciferase of photobacterium leiognathi was fo ... | 2017 | 28126438 |
| structural distinctions of fast and slow bacterial luciferases revealed by phylogenetic analysis. | bacterial luciferases are heterodimeric enzymes that catalyze a chemical reaction, so called bioluminescence, which causes light emission in bacteria. bioluminescence is vastly used as a reporter system in research tools and commercial developments. however, the details of the mechanisms that stabilize and transform the reaction intermediates as well as differences in the enzymatic kinetics amongst different bacterial luciferases remain to be elucidated. | 2016 | 27354698 |
| [the antioxidant activity of the products of processing of red grape of cabernet sauvignon, merlot, saperavi]. | experimental data on the antioxidant activity of grape juice, grape concentrates and wine from grapes of cabernet sauvignon, merlot and saperavi from crimea and krasnodar regions was presented. flavonoids are presented in the form of glycosides of such anthocyanins as delphinidin, malvidin, cyanidin, petunidin, peonidin and also by quercetin and its glycoside, (+)-d-catechin and (-)-epicatechin. oligomeric procyanidins, which are condensed catechol units (2-6) soluble in water, are presented in ... | 2016 | 27228708 |
| regulation of bioluminescence in photobacterium leiognathi strain knh6. | bacterial bioluminescence is taxonomically restricted to certain proteobacteria, many of which belong to the vibrionaceae. in the most well-studied cases, pheromone signaling plays a key role in regulation of light production. however, previous reports have indicated that certain photobacterium strains do not use this regulatory method for controlling luminescence. in this study, we combined genome sequencing with genetic approaches to characterize the regulation of luminescence in photobacteriu ... | 2015 | 26350139 |
| the transfer of reduced flavin mononucleotide from luxg oxidoreductase to luciferase occurs via free diffusion. | bacterial luciferase (luxab) is a two-component flavin mononucleotide (fmn)-dependent monooxygenase that catalyzes the oxidation of reduced fmn (fmnh(-)) and a long-chain aliphatic aldehyde by molecular oxygen to generate oxidized fmn, the corresponding aliphatic carboxylic acid, and concomitant emission of light. the luxab reaction requires a flavin reductase to generate fmnh(-) to serve as a luciferin in its reaction. however, fmnh(-) is unstable and can react with oxygen to generate h2o2, so ... | 2013 | 24004065 |
| synthesis of new 6-{[ω-(dialkylamino(heterocyclyl)alkyl]thio}-3-r-2h-[1,2,4]triazino[2,3-c]quinazoline-2-ones and evaluation of their anticancer and antimicrobial activities. | several novel 6-thio-3-r-2-oxo-2h-[1,2,4]triazino[2,3-c]quinazoline-based compounds containing an ω-(dialkylamino(heterocyclyl)]alkyl fragment were synthesized to examine their anticancer activity. some of the 6-{[ω-(hetero-cyclyl)alkyl]thio}-3-r-2h-[1,2,4]triazino[2,3-c]quinazoline-2-ones (3.1-3.10) were obtained by the nucleophilic substitution of 6-[ω-halogenalkyl]thio-3-r-2h-[1,2,4]triazino[2,3-c]quinazoline-2-ones (2.1-2.8) with azaheterocycles. alternatively, compounds 3.1-3.22 were synthe ... | 2011 | 22396903 |
| reduction kinetics of a flavin oxidoreductase luxg from photobacterium leiognathi (th1): half-sites reactivity. | bacterial bioluminescence is a phenomenon resulting from the reaction of a two-component fmn-dependent aldehyde monooxygenase system, which comprises a bacterial luciferase and a flavin reductase. bacterial luciferase (luxab) is one of the most extensively investigated two-component monooxygenases, while its reductase partner, the flavin reductase (luxg) from the same operon, has only been recently expressed in a functional form. this work reports transient kinetics identification of intermediat ... | 2010 | 20836540 |
| evaluation of acute ecotoxicity removal from industrial wastewater using a battery of rapid bioassays. | the present study compares conventional wastewater treatment technologies (coagulation-flocculation and activated sludge) and powdered activated carbon (pac) treatment for the removal of acute ecotoxicity from wastewater generated by tank truck cleaning (ttc) processes. ecotoxicity was assessed with a battery of four commercially available rapid biological toxicity testing systems, verified by the us environmental protection agency. chemical coagulation-flocculation of raw ttc wastewater had no ... | 2014 | 25521143 |
| one protein, two chromophores: comparative spectroscopic characterization of 6,7-dimethyl-8-ribityllumazine and riboflavin bound to lumazine protein. | we investigated the lumazine protein from photobacterium leiognathi in complex with its biologically active cofactor, 6,7-dimethyl-8-ribityllumazine, at different redox states and compared the results with samples containing a riboflavin cofactor. using anaerobic photoreduction, we were able to record optical absorption kinetics from both cofactors in similar protein environments. it could be demonstrated that the protein is able to stabilize a neutral ribolumazine radical with ∼35% yield. the r ... | 2014 | 25325849 |
| degradation of roxarsone in a silt loam soil and its toxicity assessment. | the land application of poultry or swine litter, containing large amounts of roxarsone, causes serious arsenic pollution in soil. understanding biotransformation process of roxarsone and its potential risks favors proper disposal of roxarsone-contaminated animal litter, yet remains not achieved. we report an experimental study of biotransformation process of roxarsone in a silt loam soil under various soil moisture and temperature conditions, and the toxicity of roxarsone and its products from d ... | 2014 | 25048898 |
| gut bacteria associated with different diets in reared nephrops norvegicus. | the impact of different diets on the gut microbiota of reared nephrops norvegicus was investigated based on bacterial 16s rrna gene diversity. specimens were collected from pagasitikos gulf (greece) and kept in experimental rearing tanks, under in situ conditions, for 6months. treatments included three diets: frozen natural (mussel) food (m), dry formulated pellet (p) and starvation (s). gut samples were collected at the initiation of the experiment, and after 3 and 6months. tank water and diet ... | 2012 | 23040460 |
| the effect of hg2+ on the bioluminescence of photobacterium leiognathi. | photobacteria were used as test objects for rapid monitoring of ecotoxicants. specific inhibitory effects of hg(2+) on bioluminescence and cell growth as well as the lux gene expression of photobacterium leiognathi were studied. the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction assay was used to evaluate cellular proliferation and mortality. the luminescent inhibition effect on p. leiognathi cells was found to increase as cellular mortality increased; y = 0.744x - 4.8916 ... | 2013 | 22777900 |
| limited geographic distribution of certain strains of the bioluminescent symbiont photobacterium leiognathi. | photobacterium leiognathi is a facultative bioluminescent symbiont of marine animals. strains of p. leiognathi that are merodiploid for the luminescence genes (lux-rib operon) have been previously obtained only from japan. in contrast, strains bearing a single lux-rib operon have been obtained from all the areas sampled in japan and the western pacific. in this study, we tested whether distribution of merodiploid p. leiognathi is limited by physical barriers in the environment, or because fish i ... | 2012 | 22404110 |
| structural and biochemical properties of luxf from photobacterium leiognathi. | the lux-operon of bioluminescent bacteria contains the genes coding for the enzymes required for light emission. some species of photobacteria feature an additional gene, luxf, which shows similarity to luxa and luxb, the genes encoding the heterodimeric luciferase. isolated dimeric luxf binds four molecules of an unusually derivatized flavin, i.e., 6-(3'-(r)-myristyl)-fmn (myrfmn). in the present study we have heterologously expressed luxf in escherichia coli bl21 in order to advance our unders ... | 2015 | 26209460 |
| determination of pyruvic acid concentration using a bioluminescence system from photobacterium leiognathi. | a novel, highly sensitive and selective bacterial luminescence method for the detection of pyruvic acid (pa) is reported here. this method is based on a reaction system catalyzed by lactate dehydrogenase (ldh) with the bacterial luciferase-fmn:nadh oxidoreductase bioluminescence system in vitro. the reduced nicotinamide adenine dinucleotide (nadh) involved in the ldh reaction system could be quantitatively analyzed by the bioluminescence system. a good linear relationship between the luminescenc ... | 2015 | 25959227 |
| the fusion vibrio campbellii luciferase as a eukaryotic gene reporter. | bacterial luciferase from vibrio campbellii is a thermostable enzyme with an in vitro thermal inactivation half-life of ~1020 min at 37°c. the enzyme also binds tightly to reduced fmn. in this study, a v. campbellii fusion luciferase construct in which the α and β subunits are linked with a decapeptide was made and characterized. in general, the overall enzymatic properties of the two enzymes are similar. expression of the enzymes in escherichia coli demonstrated that the v. campbellii fusion lu ... | 2012 | 23000378 |
| a sensitive and high throughput bacterial luminescence assay for assessing aquatic toxicity--the blt-screen. | bioassays using naturally luminescent bacteria are commonly used to assess the toxicity of environmental contaminants, detected by a decrease in luminescence. typically, this has involved the use of commercial test kits such as microtox and toxscreen. these commercial assays, however, have limitations for routine environmental monitoring, including the need for specialized equipment, a low throughput and high on-going costs. there is therefore a need to develop a bacteria bioassay that is sensit ... | 2015 | 25845535 |
| bioavailability, ecotoxicity, and geological characteristics of trace lead in sediments from two sites on negro river, uruguay, south america. | bioassays of two sites along the rio negro in uruguay indicate ecotoxicity, which could be attributable to trace concentrations of lead in river sediments. monthly samples at two sites at baygorria and bonete locations were analyzed for both particle size and lead. lead was determined by atomic spectrometry in river water and sediment and particle size by sieving and sedimentation. data showed that baygorria's sediments have greater percentage of clay than bonete's (20.4 and 5.8%, respectively). ... | 2011 | 21968803 |
| Bacterial bioluminescence as a lure for marine zooplankton and fish. | The benefits of bioluminescence for nonsymbiotic marine bacteria have not been elucidated fully. One of the most commonly cited explanations, proposed more than 30 y ago, is that bioluminescence augments the propagation and dispersal of bacteria by attracting fish to consume the luminous material. This hypothesis, based mostly on the prevalence of luminous bacteria in fish guts, has not been tested experimentally. Here we show that zooplankton that contacts and feeds on the luminescent bacterium ... | 2011 | 22203999 |
| a beta-galactoside alpha2,6-sialyltransferase produced by a marine bacterium, photobacterium leiognathi jt-shiz-145, is active at ph 8. | a gene encoding a sialyltransferase produced by photobacterium leiognathi jt-shiz-145 was cloned, sequenced, and expressed in escherichia coli. the sialyltransferase gene contained an open reading frame of 1494 base pairs (bp) encoding a predicted protein of 497 amino acid residues. the deduced amino acid sequence of the sialyltransferase had no significant similarity to mammalian sialyltransferases and did not contain sialyl motifs, but did show high homology to another marine bacterial sialylt ... | 2007 | 17704107 |