Development of biocatalysts immobilized on coal ash-derived Ni-zeolite for facilitating 4-chlorophenol degradation.
Bioresour Technol
; 307: 123201, 2020 Jul.
Article
em En
| MEDLINE
| ID: mdl-32220822
ABSTRACT
A new type of biocatalyst was developed to facilitate the biochemical decomposition of 4-chlorophenol (4-CP) in this study. Oxydoreductases that catalyze the initial steps of 4-CP biodegradation were immobilized on a synthetic inorganic enzyme support. Type-X zeolite, a high-surface area support, was synthesized from coal fly ash, on which nickel ions were plated by impregnation (Ni-zeolite), followed by the effective immobilization (77.5% immobilization yield) of recombinant monooxygenase (CphC-I), dioxygenase (CphA-I), and flavin reductase (Fre) isolated from Pseudarthrobacter chlorophenolicus A6 and Escherichia coli K-12, respectively. The retained catalytic activity of the enzymes immobilized on Ni-zeolite was as high as 64% of the value for the corresponding free enzymes. The Michaelis-Menten kinetic parameters vmax and KM of the immobilized enzymes were determined to be 0.20 mM·min-1 and 0.44 mM, respectively. These results are expected to provide useful information with respect to the development of novel enzymatic treatments for phenolic hydrocarbon contaminants.
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Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Clorofenóis
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Zeolitas
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Escherichia coli K12
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article