Document Detail

Anaerobic degradation of n-hexane in a denitrifying bacterium: further degradation of the initial intermediate (1-methylpentyl)succinate via C-skeleton rearrangement.
MedLine Citation:
PMID:  11907679     Owner:  NLM     Status:  MEDLINE    
The anaerobic degradation pathway of the saturated hydrocarbon n-hexane in a denitrifying strain (HxN1) was examined by gas chromatography-mass spectrometry of derivatized extracts from cultures grown with unlabeled and deuterated substrate; several authentic standard compounds were included for comparison. The study was focused on possible reaction steps that follow the initial formation of (1-methylpentyl)succinate from n-hexane and fumarate. 4-Methyloctanoic, 4-methyloct-2-enoic, 2-methylhexanoic, 2-methylhex-2-enoic and 3-hydroxy-2-methylhexanoic acids (in addition to a few other methyl-branched acids) were detected in n-hexane-grown but not in n-hexanoate-grown cultures. Labeling indicated preservation of the original carbon chain of n-hexane in these acids. Tracing of the deuterium label of 3- d1-(1-methylpentyl)succinate in tentative subsequent products indicated a deuterium/carboxyl carbon exchange in the succinate moiety. This suggests that the metabolism of (1-methylpentyl)succinate employs reactions analogous to those in the established conversion of succinyl-CoA via methylmalonyl-CoA to propionyl-CoA. Accordingly, a pathway is proposed in which (1-methylpentyl)succinate is converted to the CoA-thioester, rearranged to (2-methylhexyl)malonyl-CoA and decarboxylated (perhaps by a transcarboxylase) to 4-methyloctanoyl-CoA. The other identified fatty acids match with a further degradation of 4-methyloctanoyl-CoA via rounds of conventional beta-oxidation. Such a pathway would also allow regeneration of fumarate (for n-hexane activation) from propionyl-CoA formed as intermediate and hence present a cyclic process.
Heinz Wilkes; Ralf Rabus; Thomas Fischer; Antje Armstroff; Astrid Behrends; Friedrich Widdel
Related Documents :
15652569 - Biochemical characterization of elongase activity in corn (zea mays l.) roots.
12435399 - Beta-adrenergic stimulation controls the expression of a thioesterase specific for very...
3355159 - Micellization of fatty acyl-coa mixtures and its relevance to the fatty acyl selectivit...
2906959 - Mechanisms by which tumor necrosis factor stimulates hepatic fatty acid synthesis in vivo.
18799749 - The very-long-chain hydroxy fatty acyl-coa dehydratase pasticcino2 is essential and lim...
880699 - Selenium inhibition of avian fatty acid synthetase complex.
3709479 - Methanol extract of grain dust shows complement fixing activity and other characteristi...
16657579 - The effect of water stress on indoleacetic acid oxidase in pea plants.
20921909 - A trial to assess the efficacy of glutamic acid in prevention of vincristine-induced ne...
Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, Non-U.S. Gov't     Date:  2001-12-14
Journal Detail:
Title:  Archives of microbiology     Volume:  177     ISSN:  0302-8933     ISO Abbreviation:  Arch. Microbiol.     Publication Date:  2002 Mar 
Date Detail:
Created Date:  2002-03-21     Completed Date:  2002-04-26     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0410427     Medline TA:  Arch Microbiol     Country:  Germany    
Other Details:
Languages:  eng     Pagination:  235-43     Citation Subset:  IM    
Institut für Erdöl und Organische Geochemie, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Alkanes / analysis,  metabolism*
Bacteria / growth & development,  metabolism*
Culture Media
Fumarates / metabolism
Gas Chromatography-Mass Spectrometry
Hexanes / chemistry,  metabolism*
Hexanoic Acids / metabolism
Nitrates / metabolism
Succinates / analysis,  metabolism*
Reg. No./Substance:
0/(1-methylpentyl)succinate; 0/Alkanes; 0/Culture Media; 0/Fumarates; 0/Hexanes; 0/Hexanoic Acids; 0/Nitrates; 0/Succinates; 110-17-8/fumaric acid; 110-54-3/n-hexane; 142-62-1/hexanoic acid; 7782-39-0/Deuterium

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Membrane association of Klebsiella pneumoniae NifL is affected by molecular oxygen and combined nitr...
Next Document:  Isolation, characterization, and fermentative pattern of a novel thermotolerant Prototheca zopfii va...