Elucidation of multiple alkane hydroxylase systems in biodegradation of crude oil n-alkane pollution by Pseudomonas aeruginosa DN1.
J Appl Microbiol
; 128(1): 151-160, 2020 Jan.
Article
em En
| MEDLINE
| ID: mdl-31566849
ABSTRACT
AIMS:
The purpose of this study was to elucidate the characteristics of multiple alkane hydroxylase systems in Pseudomonas aeruginosa DN1, including two homologues of AlkB (AlkB1 and AlkB2 ), a CYP153 homologue (P450), and two homologues of Alm-like (AlmA1 and AlmA2 ). METHODS ANDRESULTS:
DN1 was capable of utilizing diverse n-alkanes with chain lengths from 8 to 40 C atoms as the sole carbon source, and displayed high degradation efficiency (ï¼85%) of crude oil and a majority of n-alkanes using gas chromatography method. RT-qPCR analysis showed that the five enzyme genes could be induced by n-alkanes ranging from medium-chain length to long-chain length which indicated the dissimilarity of expression between those genes when grown on different n-alkanes. Notably, the expression of alkB2 gene was upregulated in the presence of all of the tested n-alkanes, particularly responded to long-chain n-alkanes like C20 and C32 . Meanwhile, long-chain n-alkanes (C20 -C36 ) significantly elevated cyp153 expression level, and the expression of two almA genes was only upregulated in the presence of n-alkanes with chain lengths of 20C's and longer. Furthermore, the disruption of those genes demonstrated that AlkB2 appeared to play a key role in the biodegradation of substrates of a broad-chain length ranges, besides other alkane hydroxylase systems ensured the utilization of n-alkanes with chain lengths of from 20 to 40 C atoms.CONCLUSION:
The five functional alkane hydroxylase genes make DN1 an attractive option for its versatile alkane degradation, which is primarily dependent on the expression of alkB2 . SIGNIFICANCE AND IMPACT OF THE STUDY Our findings suggest that P. aeruginosa DN1 is a predominately potential long-chain n-alkane-degrading bacterium with multiple alkane hydroxylase systems in crude oil-contaminated environment.Palavras-chave
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Pseudomonas aeruginosa
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Proteínas de Bactérias
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Petróleo
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Citocromo P-450 CYP4A
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Alcanos
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article