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Metabolites of the Anaerobic Degradation of n-Hexane by Denitrifying Betaproteobacterium Strain HxN1.

ABSTRACT: The constitutions of seven metabolites formed during anaerobic degradation of n-hexane by the denitrifying betaproteobacterium strain HxN1 were elucidated by comparison of their GC and MS data with those of synthetic reference standards. The synthesis of 4-methyloctanoic acid derivatives was accomplished by the conversion of 2-methylhexanoyl chloride with Meldrum's acid. The ?-oxoester was reduced with NaBH₄ , the hydroxy group was eliminated, and the double bond was displaced to yield the methyl esters of 4-methyl-3-oxooctanoate, 3-hydroxy-4-methyloctanoate, (E)-4-methyl-2-octenoate, and (E)- and (Z)-4-methyl-3-octenoate. The methyl esters of 2-methyl-3-oxohexanoate and 3-hydroxy-2-methylhexanoate were similarly prepared from butanoyl chloride and Meldrum's acid. However, methyl (E)-2-methyl-2-hexenoate was prepared by Horner-Wadsworth-Emmons reaction, followed by isomerization to methyl (E)-2-methyl-3-hexenoate. This investigation, with the exception of 4-methyl-3-oxooctanoate, which was not detectable in the cultures, completes the unambiguous identification of all intermediates of the anaerobic biodegradation of n-hexane to 2-methyl-3-oxohexanoyl coenzyme?A (CoA), which is then thiolytically cleaved to butanoyl-CoA and propionyl-CoA; these two metabolites are further transformed according to established pathways.

SUBMITTER: Kuppers J

PROVIDER: S-EPMC7028053 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Metabolites of the Anaerobic Degradation of n-Hexane by Denitrifying Betaproteobacterium Strain HxN1.

Küppers Julian J Mitschke Nico N Heyen Simone S Rabus Ralf R Wilkes Heinz H Christoffers Jens J

Chembiochem : a European journal of chemical biology 20191030 3

The constitutions of seven metabolites formed during anaerobic degradation of n-hexane by the denitrifying betaproteobacterium strain HxN1 were elucidated by comparison of their GC and MS data with those of synthetic reference standards. The synthesis of 4-methyloctanoic acid derivatives was accomplished by the conversion of 2-methylhexanoyl chloride with Meldrum's acid. The β-oxoester was reduced with NaBH<sub>4</sub> , the hydroxy group was eliminated, and the double bond was displaced to yiel ...[more]

PMID: 31294892

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Dataset Information

Metabolites of the Anaerobic Degradation of n-Hexane by Denitrifying Betaproteobacterium Strain HxN1.

Publications

Metabolites of the Anaerobic Degradation of n-Hexane by Denitrifying Betaproteobacterium Strain HxN1.

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