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ABSTRACT: Growth and emission characteristics of the luminescent bacterium Photobacterium phosphoreum strain KM MGU 331 originating from the White Sea and isolated from the intestine of a bottom-dwelling fish, the European
sculpin, Myoxocephalus scorpius, were analyzed. The strain is characterized by a high rate of colony formation and high intensity of light emission on agarized
medium at 4° C as well as by highly efficient (5 × 105 quanta s−1 cell−1) and prolonged (over 100 h) light generation upon submerged cultivation at 20°C. The acidic shift of pH in the medium didn’t
exceed 0.3 pH units. Effects of temperature, pH, and sodium chloride concentration on emission characteristics of intact photobacterium
cells were studied. The optimal temperature for luminescence was found to be 15°C. The maximum luminescence activity was stable
in a wide pH range from 7.0 to 9.0. Luminescence occurred within the range of 0.2–3.8% NaCl with the maximum at 2.5%. The
results obtained confirm the literature data suggesting that luminescent bacteria adapted to low-temperature conditions possess
a highly conjugated system of electron transfer to luciferase.
Microbiology 04/2012; 78(5):554-558. · 3.06 Impact Factor
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ABSTRACT: Photobacteria were used as a test object for rapid monitoring of ecotoxicants. Specific inhibitory effects of phenol and its
chlorinated derivatives (2-chlorophenol, 2,3-dichlorophenol, pentachlorophenol, 2,4-dichlorophenoxyacetic acid, and 2,4,5-trichlorophenoxyacetic
acid) on bioluminescence and respiration of intact cells, as well as on the emission activity of the bioluminescence system
and luciferase itself, were studied. The toxic effect on the photobacterial cells was found to increase as the number of chlorine
atoms in the chlorophenol molecule increased. However, this trend was not observed in cell-free systems (purified luciferase
or the protein fraction of a cell-free extract treated with (NH4)2SO4 at 40–75% saturation). Bacterial cells have a higher threshold sensitivity to chlorophenols in comparison to the sensitivity
of the bioluminescence enzyme system or luciferase. Neutral phenols inhibit luciferase by competing with decanal, whereas
a mixed mechanism of inhibition with this substrate is typical of phenoxyacetic acids. With respect to FMNH2, all chlorophenols tested in this work were uncompetitive inhibitors. Oxygen uptake by photobacteria was shown to be insensitive
to chlorophenols, at least within the concentration range that was effective in bioluminescence inhibition. The results of
this study suggest that the bacterial bioluminescence system is not the primary target of the chlorophenol-induced effect
on photobacteria.
Applied Biochemistry and Microbiology 04/2012; 36(4):404-408. · 0.56 Impact Factor
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ABSTRACT: Kinetic characteristics of light emission by intact cells of photobacteria Photobacterium phosphoreum and Vibrio harveyi were studied (at pH 5.5, 7.0, and 8.0), as well as inhibitory effects of 2,4-di- and 2,4,5-triphenoxyacetic acids (2,4-D
and 2,4,5-T), pentachlorophenol (PCP), and 2,6-dimethylphenol (2,6-DMP) (at the same pH values). The emission kinetics lacked
a steady state, irrespective of pH. At pH 5.5, luminescence decayed exponentially in the 60-s range; at pH 7.0 and 8.0, a
5-min luminescence activation was observed. The respiratory activity of the cells decreased by more than an order of magnitude
at pH 5.5 (compared to the levels observed at pH 7.0 and 8.0). The inhibitory effects of 2,4-D, 2,4,5-T, and PCP differed
by one to two orders of magnitude, depending on pH. Maximum cell sensitivity to these compounds appeared at pH 5.5; minimum
sensitivity, at pH 8.0. The effect of 2,6-DMP was pH-independent. The inhibitory effect was determined by the hydrophobicity
of the molecule and pK values of the toxicants. At all pH values, substrate-depleted cells of photobacteria were more sensitive
to chlorophenolic compounds than cells supplied with energy.
Applied Biochemistry and Microbiology 01/2005; 41(6):563-569. · 0.56 Impact Factor
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Biotechnology (Reading, Mass.) 02/1989; 11:39-78.
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ABSTRACT: The effect of various xenobiotic substrates of microsomal cytochrome P-450, including dimethylaniline, ethylmorphine, hexabarbital and aminopyrine, on the bioluminescence of the bacteria Vibrio fischeri and the bacterial luciferase mixed-function oxidase system is described. These compounds are effective inhibitors of the luminescence reaction. The inhibition provided evidence for the competitive nature of the interactions between xenobiotics and an aliphatic aldehyde, which is a substrate of bacterial luciferase, at the binding site for cytochrome P-450. The bioluminescence method is suitable for the analysis of metabolism and detoxication of various xenobiotics.
Xenobiotica 05/1985; 15(4):271-6. · 1.79 Impact Factor
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ABSTRACT: Properties of a coupled system "LDH-bacterial luciferase" were studied. The light-generating enzymatic system from luminescent bacteria Photobacterium fisheri was used as an indicator of the dehydrogenase activity. Kinetic parameters of the coupled system were studied using commercially available preparation of LDH and the enzyme from human blood plasma. The luminescent activity of bacterial preparation was shown to correlate with the activity of LDH and its isoenzymes within wide range of blood plasma concentrations.
Voprosy medit͡sinskoĭ khimii 02/1984; 30(6):45-50.
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Doklady Akademii nauk SSSR 02/1983; 270(5):1239-42.
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ABSTRACT: The quenching of luminescence of bacterial luciferase from Photobacterium fischeri by non-specific electron acceptors and inhibitors of dehydrogenases was studied. The inhibition of the luminescent reaction obeys the non-competitive mechanism with NADH, FMN and aliphatic aldehyde. The inhibitors compete with cytochrome c for NADH -- cytochrome c oxido-reductase. It is concluded that lumiredoxin, a FeS-containing protein, is the most sensitive component of the luminescent electron transport chain.
Biokhimii͡a (Moscow, Russia) 02/1981; 46(1):40-6.
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ABSTRACT: The composition of cytochromes was studied in Photobacterium fischeri 6 at different growth phases and under various conditions of cultivation. The electron transport chains of the bacterium are characterized by the presence of cytochromes b and c types. The terminal oxidases are cytochromes o, a2+a1 and P-450. The hemoprotein P-450 functions as a mixed function oxidase. The qualitative composition of cytochromes does not depend on the growth phase of the bacterium but does on the conditions of cultivation. The bacterium synthesizes cytochromes a2+a1 in the conditions of oxygen deficiency. The synthesis of cytochrome o depends on the composition of the medium.
Mikrobiologiia 49(3):377-82.
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ABSTRACT: Kinetic characteristics of light emission by intact cells of the photobacteria Photobacterium phosphoreum and Vibrio harveyi at pH 5.5, 7.0, and 8.0 were studied as well as specific features of inhibitory effects of 2,4-di- and 2,4,5-triphenoxyacetic acids (2,4-D and 2,4,5-T), pentachlorophenol (PCP), and 2,6-dimethylphenol (2,6-DMP) at the same pH values. Nonstationarity of emission kinetics was observed at all the pH values studied. Exponential luminescence decay in a 60-sec range was observed at pH 5.5; a 5-min luminescence activation, at pH 7.0 and 8.0. The cell respiratory activity drops by over one order of magnitude at pH 5.5 compared with the activities at pH 7.0 and 8.0. The inhibitory effects of 2,4-D, 2,4,5-T, and PCP differ by one-two orders of magnitude depending on pH. The maximal cell sensitivity to these compounds appears at pH 5.5; the minimal, at pH 8.0. The effect of 2,6-DMP is independent of pH. As is demonstrated, it is hydrophobicity of the molecule and pK values of the toxicants that determine the inhibitory effect. Characteristic of the substrate-starved photobacterial cells are higher sensitivity to chlorophenolic compounds compared with the cells provided with high energy supply at all the pH values.
Prikladnaia biokhimiia i mikrobiologiia 41(6):640-6.
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[show abstract]
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ABSTRACT: Photobacteria were used as a test object for rapid monitoring of ecotoxicants. Specific inhibitory effects of phenol and its chlorinated derivatives (2-chlorophenol, 2,3-dichlorophenol, pentachlorophenol, 2,4-dichlorophenoxyacetic acid, and 2,4,5-trichlorophenoxyacetic acid) on bioluminescence and respiration of intact cells, as well as on the emission activity of the bioluminescence system and luciferase itself, were studied. The toxic effect on the photobacterial cells was found to increase as the number of chlorine atoms in the chlorophenol molecule increases. However, this trend was not observed in cell-free systems (purified luciferase or the protein fraction of a cell-free extract treated with (NH)4SO4 at 40-75% saturation). Bacterial cells have a higher threshold sensitivity to chlorophenols in comparison to the sensitivity of the bioluminescence enzyme system or luciferase. Neutral phenols inhibit luciferase by competing with decanal, whereas a mixed mechanism of inhibition with this substrate is typical of phenoxyacetic acids. With respect to FMNH2, all chlorophenols tested in this work were uncompetitive inhibitors. Oxygen uptake by photobacteria was shown to be insensitive to chlorophenols, at least within the concentration range that was effective in bioluminescence inhibition. The results of this study suggest that bacterial bioluminescence system is not the primary target of the chlorophenol-induced effect on photobacteria.
Prikladnaia biokhimiia i mikrobiologiia 36(4):469-73.
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ABSTRACT: The bioluminescent activity of intact Vibrio harveyi cells loaded with different concentrations of NaCl and KCl at different pH values was studied. In the pH range of 6.5-8.5, the effect of Na+ was significantly higher than that of K+ at all concentrations studied. Maximum luminescent activity was observed in cells loaded with 0.68 M NaCl. When Na+ was nonuniformly distributed on the plasma membrane, the cell luminescence kinetics was nonstationary in the 20-min range: during incubation, the luminescence intensity increased at pH 6.5 and decreased at pH 8.5. The activation and damping rate constants depended on the Na+ gradient value. The maximum of luminescent activity shifted during incubation from pH 8.5 to 6.5-7.0. The luminescence kinetics in the systems with KCl was stationary; the maximum level of luminescence was observed in the pH range of 7.0-7.5. Under Na(+)-controlled conditions, the cell respiration and luminescence changed in synchronism. The protonophore CCP at a concentration of 20 microM completely inhibited luminescence at pH 6.5 and was ineffective at pH 8.5.
Mikrobiologiia 70(4):525-30.
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ABSTRACT: The hemoprotein composition of the luminescent bacterium Photobacterium fischeri was studied, in particular, the distribution of cytochromes among the bacterial fractions, viz. cell-free extract, supernatant, "particles", protein preparation. The hemochromogenic analysis has shown that the principal hemoproteins of Photobacterium fischeri are cytochromes, with hemes of the b and c type. The activity of luciferase is distributed with hemoproteins. The purified preparation of luciferase contains cytochrome of the b type that has been identified as mixed functions oxidase--P-450.
Mikrobiologiia 49(4):477-82.
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ABSTRACT: At 22 degrees C the bioluminescence decay kinetics in the in vitro reaction catalysed by Vibrio harveyi luciferase in the presence of different aldehydes--nonanal, decanal, tridecanal and tetradecanal did not follow the simple exponential pattern and could be fitted to a two-exponential process. One more principal distinction from the first-order kinetics is the dependence of the parameters on aldehyde concentration. The complex bioluminescence decay kinetics are interpreted in terms of a scheme, where bacterial luciferase is able to perform multiple turnovers using different flavin species to produce light. The initial phase of the bioluminescent reaction appears to proceed mainly with fully reduced flavin as the substrate while the final one results from the involvement of flavin semiquinone in the catalytic cycle.
Journal of Bioluminescence and Chemiluminescence 5(3):213-7.
