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Enzymes involved in vinyl acetate decomposition by Pseudomonas fluorescens PCM 2123 strain.

Szczyrba E, Greń I, Bartelmus G - Folia Microbiol. (Praha) (2013)

Bottom Line: Comparison of Km values for alcohol and aldehyde dehydrogenases for acetaldehyde suggested that this metabolite was preferentially oxidized than reduced.Activity of alcohol dehydrogenase reducing acetaldehyde to ethanol suggested that one mechanism of defense against the elevated concentration of toxic acetaldehyde could be its temporary reduction to ethanol.Esterase activity was inhibited by phenylmethanesulfonyl fluoride, while β-mercaptoethanol, dithiothreitol, and ethylenediaminetetraacetic acid had no inhibitor effect.

View Article: PubMed Central - PubMed

Affiliation: Institute of Chemical Engineering, Polish Academy of Sciences, Bałtycka 5, 44-100, Gliwice, Poland.

ABSTRACT
Esterases are widely used in food processing industry, but there is little information concerning enzymes involved in decompositions of esters contributing to pollution of environment. Vinyl acetate (an ester of vinyl alcohol and acetic acid) is a representative of volatile organic compounds (VOCs) in decomposition, of which hydrolyses and oxidoreductases are mainly involved. Their activities under periodically changing conditions of environment are essential for the removal of dangerous VOCs. Esterase and alcohol/aldehyde dehydrogenase activities were determined in crude cell extract from Pseudomonas fluorescens PMC 2123 after vinyl acetate induction. All examined enzymes exhibit their highest activity at 30-35 °C and pH 7.0-7.5. Esterase preferably hydrolyzed ester bonds with short fatty chains without plain differences for C2 or C4. Comparison of Km values for alcohol and aldehyde dehydrogenases for acetaldehyde suggested that this metabolite was preferentially oxidized than reduced. Activity of alcohol dehydrogenase reducing acetaldehyde to ethanol suggested that one mechanism of defense against the elevated concentration of toxic acetaldehyde could be its temporary reduction to ethanol. Esterase activity was inhibited by phenylmethanesulfonyl fluoride, while β-mercaptoethanol, dithiothreitol, and ethylenediaminetetraacetic acid had no inhibitor effect. From among metal ions, only Mg(2+) and Fe(2+) stimulated the cleavage of ester bond.

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Effect of temperature (a) and pH (b) on specific activities of dehydrogenase from PCM 2123 cells, where: alcohol dehydrogenase (ethanol) (open triangle), alcohol dehydrogenase (acetaldehyde) (open circle), aldehyde dehydrogenase (open diamond)
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Fig3: Effect of temperature (a) and pH (b) on specific activities of dehydrogenase from PCM 2123 cells, where: alcohol dehydrogenase (ethanol) (open triangle), alcohol dehydrogenase (acetaldehyde) (open circle), aldehyde dehydrogenase (open diamond)

Mentions: The optima temperatures for activities of dehydrogenases from PCM 2123 cells were at 30 °C (Fig. 3a), and an aldehyde dehydrogenase was the only one which lost almost 80 % of its activity when temperature decreased to 20 °C.Fig. 4


Enzymes involved in vinyl acetate decomposition by Pseudomonas fluorescens PCM 2123 strain.

Szczyrba E, Greń I, Bartelmus G - Folia Microbiol. (Praha) (2013)

Effect of temperature (a) and pH (b) on specific activities of dehydrogenase from PCM 2123 cells, where: alcohol dehydrogenase (ethanol) (open triangle), alcohol dehydrogenase (acetaldehyde) (open circle), aldehyde dehydrogenase (open diamond)
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3936133&req=5

Fig3: Effect of temperature (a) and pH (b) on specific activities of dehydrogenase from PCM 2123 cells, where: alcohol dehydrogenase (ethanol) (open triangle), alcohol dehydrogenase (acetaldehyde) (open circle), aldehyde dehydrogenase (open diamond)
Mentions: The optima temperatures for activities of dehydrogenases from PCM 2123 cells were at 30 °C (Fig. 3a), and an aldehyde dehydrogenase was the only one which lost almost 80 % of its activity when temperature decreased to 20 °C.Fig. 4

Bottom Line: Comparison of Km values for alcohol and aldehyde dehydrogenases for acetaldehyde suggested that this metabolite was preferentially oxidized than reduced.Activity of alcohol dehydrogenase reducing acetaldehyde to ethanol suggested that one mechanism of defense against the elevated concentration of toxic acetaldehyde could be its temporary reduction to ethanol.Esterase activity was inhibited by phenylmethanesulfonyl fluoride, while β-mercaptoethanol, dithiothreitol, and ethylenediaminetetraacetic acid had no inhibitor effect.

View Article: PubMed Central - PubMed

Affiliation: Institute of Chemical Engineering, Polish Academy of Sciences, Bałtycka 5, 44-100, Gliwice, Poland.

ABSTRACT
Esterases are widely used in food processing industry, but there is little information concerning enzymes involved in decompositions of esters contributing to pollution of environment. Vinyl acetate (an ester of vinyl alcohol and acetic acid) is a representative of volatile organic compounds (VOCs) in decomposition, of which hydrolyses and oxidoreductases are mainly involved. Their activities under periodically changing conditions of environment are essential for the removal of dangerous VOCs. Esterase and alcohol/aldehyde dehydrogenase activities were determined in crude cell extract from Pseudomonas fluorescens PMC 2123 after vinyl acetate induction. All examined enzymes exhibit their highest activity at 30-35 °C and pH 7.0-7.5. Esterase preferably hydrolyzed ester bonds with short fatty chains without plain differences for C2 or C4. Comparison of Km values for alcohol and aldehyde dehydrogenases for acetaldehyde suggested that this metabolite was preferentially oxidized than reduced. Activity of alcohol dehydrogenase reducing acetaldehyde to ethanol suggested that one mechanism of defense against the elevated concentration of toxic acetaldehyde could be its temporary reduction to ethanol. Esterase activity was inhibited by phenylmethanesulfonyl fluoride, while β-mercaptoethanol, dithiothreitol, and ethylenediaminetetraacetic acid had no inhibitor effect. From among metal ions, only Mg(2+) and Fe(2+) stimulated the cleavage of ester bond.

Show MeSH