Kinetics of a rapid, luminol dependent chemiluminescence signal induced in HL-60 cells by amphotericin B and other stimulants

Addition of the polyene antibiotic amphotericin B or tissue culture medium to nondifferentiated HL-60 cells in the presence of luminol induces a chemiluminescence signal that reaches a peak value within a few seconds and decays exponentially in less than a minute. The kinetics of the signal and its modulation by superoxide dismutase, catalase, and horseradish peroxidase are consistent with a series of solution biochemical processes with a rate-determining step corresponding to the disproportionation of a luminal–superoxide complex. The effects of the enzymes demonstrate that superoxide is a precursor to the rate-determining intermediate and that both catalase and peroxide enhance a reaction that competes with the rate-limiting process.Key words: chemiluminescence, luminol, amphotericin B, superoxide, HL-60 cells.

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Superoxide-dependent consumption of nitric oxide in biological media may confound in vitro experiments

Biochemical Journal ◽

10.1042/bj20020933 ◽

2003 ◽

Vol 369 (2) ◽

pp. 399-406 ◽

Cited By ~ 39

Author(s):

Robert G. KEYNES ◽

Charmaine GRIFFITHS ◽

John GARTHWAITE

Keyword(s):

Tissue Culture ◽

Superoxide Dismutase ◽

Culture Medium ◽

Superoxide Radical ◽

Cultured Cells ◽

Soluble Guanylate Cyclase ◽

Subsequent Reaction ◽

Biological Media ◽

State Concentration

NO functions ubiquitously as a biological messenger but has also been implicated in various pathologies, a role supported by many reports that exogenous or endogenous NO can kill cells in tissue culture. In the course of experiments aimed at examining the toxicity of exogenous NO towards cultured cells, we found that most of the NO delivered using a NONOate (diazeniumdiolate) donor was removed by reaction with the tissue-culture medium. Two NO-consuming ingredients were identified: Hepes buffer and, under laboratory lighting, the vitamin riboflavin. In each case, the loss of NO was reversed by the addition of superoxide dismutase. The effect of Hepes was observed over a range of NONOate concentrations (producing up to 1μM NO). Furthermore, from measurements of soluble guanylate cyclase activity, Hepes-dependent NO consumption remained significant at the low nanomolar NO concentrations relevant to physiological NO signalling. The combination of Hepes and riboflavin (in the light) acted synergistically to the extent that, instead of a steady-state concentration of about 1μM being generated, NO was undetectable (<10nM). Again, the consumption could be inhibited by superoxide dismutase. A scheme is proposed whereby a ‘vicious cycle’ of superoxide radical (O2•-) formation occurs as a result of oxidation of Hepes to its radical species, fuelled by the subsequent reaction of O2•- with NO to form peroxynitrite (ONOO-). The inadvertent production of ONOO- and other reactive species in biological media, or the associated loss of NO, may contribute to the adverse effects, or otherwise, of NO in vitro.

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Association of Induced Disease Resistance of Rhododendron Seedlings with Inoculation of Streptomyces sp. R-5 and Treatment with Actinomycin D and Amphotericin B to the Tissue-culture Medium.

The Journal of Antibiotics ◽

10.7164/antibiotics.54.501 ◽

2001 ◽

Vol 54 (6) ◽

pp. 501-505 ◽

Cited By ~ 21

Author(s):

MASAFUMI SHIMIZU ◽

TAMOTSU FURUMAI ◽

YASUHIRO IGARASHI ◽

HIROYASU ONAKA ◽

TOMIO NISHIMURA ◽

...

Keyword(s):

Tissue Culture ◽

Disease Resistance ◽

Amphotericin B ◽

Culture Medium ◽

Actinomycin D ◽

Tissue Culture Medium ◽

Streptomyces Sp ◽

Induced Disease Resistance

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Effect of Aggregation on the Kinetics of Autoxidation of the Polyene Antibiotic Amphotericin B

Journal of Pharmaceutical Sciences ◽

10.1002/jps.2600820209 ◽

1993 ◽

Vol 82 (2) ◽

pp. 162-166 ◽

Cited By ~ 25

Author(s):

Lamy-Freund M.Teresa ◽

Vergínia F.N. Ferreira ◽

Faljoni-Alárlo Adelaide ◽

Shirley Schreier

Keyword(s):

Amphotericin B ◽

Polyene Antibiotic ◽

Kinetics Of

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Microbial Biofilms and Biotechnology – Some Perceptions

Current Biotechnology ◽

10.2174/2211550109999201026091512 ◽

2020 ◽

Vol 09 ◽

Author(s):

Subba Rao Toleti

Keyword(s):

Tissue Culture ◽

Synthetic Biology ◽

Industrial Effluents ◽

Aquatic Environments ◽

Biochemical Processes ◽

Microbial Biofilms ◽

Biofilm Bacteria ◽

Prophylactic Vaccines ◽

Design Construction

: The review is an attempt to introduce the readers in brief about biofilms and their implications as well as some new perceptions in biotechnology. Biofilms are adherent microbial communities, which are developed on submerged surfaces in aquatic environments. Biofilms play a significant role in exopolymer production, material deterioration and also cause harmful infections. Further, the role of corrosion causing biofilm bacteria in deterioration of different materials, microbial biofilms and their enzymatic processes in reducing the toxicity of pollutants in industrial effluents are elaborated, along with clean technologies for wastewater treatment. Biotechnology is defined as any technological application that uses biological systems to synthesize or modify products or processes. The applications include biochemical processes, medical care, cell and tissue culture as well as synthetic biology and others. Synthetic biology details about the design, construction of new biological components and systems for useful purposes. Finally, to overcome the limitations that are inherent to the use of cellular host’s, cell-free systems as critical platforms for synthetic biology applications. This mini-review also mentions about new diagnostic products based on enzymes, monoclonal antibodies and engineered proteins as well as novel prophylactic vaccines.

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Kinetics of cyclization of S-ethoxycarbonylmethylisothiouronium chloride to 2-imino-4-thiazolidone

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19790912 ◽

1979 ◽

Vol 44 (3) ◽

pp. 912-917 ◽

Cited By ~ 1

Author(s):

Vladimír Macháček ◽

Said A. El-bahai ◽

Vojeslav Štěrba

Keyword(s):

Hydrochloric Acid ◽

Dilute Hydrochloric Acid ◽

Base Catalysis ◽

General Base ◽

Rate Limiting Step ◽

Limiting Step ◽

Kinetics Of Formation ◽

Acid Catalyzed ◽

Rate Limiting ◽

Kinetics Of

Kinetics of formation of 2-imino-4-thiazolidone from S-ethoxycarbonylmethylisothiouronium chloride has been studied in aqueous buffers and dilute hydrochloric acid. The reaction is subject to general base catalysis, the β value being 0.65. Its rate limiting step consists in acid-catalyzed splitting off of ethoxide ion from dipolar tetrahedral intermediate. At pH < 2 formation of this intermediate becomes rate-limiting; rate constant of its formation is 2 . 104 s-1.

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Kinetics of carbon monoxide methanation on a Ni/SiO2 catalyst

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19901678 ◽

1990 ◽

Vol 55 (7) ◽

pp. 1678-1685

Author(s):

Vladimír Stuchlý ◽

Karel Klusáček

Keyword(s):

Carbon Monoxide ◽

Reaction Rate ◽

Catalyst Activity ◽

Adsorbed Hydrogen ◽

Reaction Products ◽

Co Methanation ◽

Molar Ratios ◽

Rate Determining Step ◽

Higher Temperature ◽

Kinetics Of

Kinetics of CO methanation on a commercial Ni/SiO2 catalyst was evaluated at atmospheric pressure, between 528 and 550 K and for hydrogen to carbon monoxide molar ratios ranging from 3 : 1 to 200 : 1. The effect of reaction products on the reaction rate was also examined. Below 550 K, only methane was selectively formed. Above this temperature, the formation of carbon dioxide was also observed. The experimental data could be described by two modified Langmuir-Hinshelwood kinetic models, based on hydrogenation of surface CO by molecularly or by dissociatively adsorbed hydrogen in the rate-determining step. Water reversibly lowered catalyst activity and its effect was more pronounced at higher temperature.

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Kinetics and mechanism of cyclization of N-(2-methoxycarbonylphenyl)-N’-methylsulphonamide to 3-methyl-(1H)-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19911701 ◽

1991 ◽

Vol 56 (8) ◽

pp. 1701-1710 ◽

Cited By ~ 4

Author(s):

Jaromír Kaválek ◽

Vladimír Macháček ◽

Miloš Sedlák ◽

Vojeslav Štěrba

Keyword(s):

Potassium Hydroxide ◽

Acid Catalysis ◽

Potassium Hydroxide Solution ◽

Hydroxide Solution ◽

General Base ◽

Rate Limiting Step ◽

Limiting Step ◽

Cyclization Kinetics ◽

Rate Limiting ◽

Kinetics Of

The cyclization kinetics of N-(2-methylcarbonylphenyl)-N’-methylsulfonamide (IIb) into 3-methyl-(1H)-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide (Ib) has been studied in ethanolamine, morpholine, and butylamine buffers and in potassium hydroxide solution. The cyclization is subject to general base and general acid catalysis. The value of the Bronsted coefficient β is about 0.1, which indicates that splitting off of the proton from negatively charged tetrahedral intermediate represents the rate-limiting and thermodynamically favourable step. In the solutions of potassium hydroxide the cyclization of dianion of the starting ester IIb probably becomes the rate-limiting step.

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Kinetic analysis of mechanism of intestinal Na+-dependent sugar transport

AJP Cell Physiology ◽

10.1152/ajpcell.1985.248.5.c498 ◽

1985 ◽

Vol 248 (5) ◽

pp. C498-C509 ◽

Cited By ~ 23

Author(s):

D. Restrepo ◽

G. A. Kimmich

Keyword(s):

Experimental Data ◽

Steady State ◽

Sugar Transport ◽

Enzyme Kinetic ◽

Steady State Distribution ◽

State Distribution ◽

Least Squares Fit ◽

Coupling Stoichiometry ◽

Rate Limiting ◽

Kinetics Of

Zero-trans kinetics of Na+-sugar cotransport were investigated. Sugar influx was measured at various sodium and sugar concentrations in K+-loaded cells treated with rotenone and valinomycin. Sugar influx follows Michaelis-Menten kinetics as a function of sugar concentration but not as a function of Na+ concentration. Nine models with 1:1 or 2:1 sodium:sugar stoichiometry were considered. The flux equations for these models were solved assuming steady-state distribution of carrier forms and that translocation across the membrane is rate limiting. Classical enzyme kinetic methods and a least-squares fit of flux equations to the experimental data were used to assess the fit of the different models. Four models can be discarded on this basis. Of the remaining models, we discard two on the basis of the trans sodium dependence and the coupling stoichiometry [G. A. Kimmich and J. Randles, Am. J. Physiol. 247 (Cell Physiol. 16): C74-C82, 1984]. The remaining models are terter ordered mechanisms with sodium debinding first at the trans side. If transfer across the membrane is rate limiting, the binding order can be determined to be sodium:sugar:sodium.

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