title: Mechanism of anaerobic degradation of triethanolamine by a homoacetogenic bacterium.
abstract: Triethanolamine (TEA) is converted into acetate and ammonia by a strictly anaerobic, gram-positive Acetobacterium strain LuTria3. Fermentation experiments with resting cell suspensions and specifically deuterated substrates indicate that in the acetate molecule the carboxylate and the methyl groups correspond to the alcoholic function and to its adjacent methylene group, respectively, of the 2-hydroxyethyl unit of TEA. A 1,2 shift of a hydrogen (deuterium) atom from -CH2-O- to =N-CH2- without exchange with the medium was observed. This fact gives evidence that a radical mechanism occurs involving the enzyme and/or coenzyme molecule as a hydrogen carrier. Such a biodegradation appears analogous to the conversion of 2-phenoxyethanol into acetate mediated by another strain of the anaerobic homoacetogenic bacterium Acetobacterium.
authors.affiliation: Dipartimento di Chimica Organica e Industriale, Università degli Studi di Milano, via Venezian 21, I-20133 Milano, Italy. giovanna.speranza@unimi.it
authors.forename: Giovanna
authors.initials: G
authors.lastname: Speranza
authors.forename: Carlo F
authors.initials: CF
authors.lastname: Morelli
authors.forename: Paola
authors.initials: P
authors.lastname: Cairoli
authors.forename: Britta
authors.initials: B
authors.lastname: Müller
authors.forename: Bernhard
authors.initials: B
authors.lastname: Schink
mesh_terms: D000079:Acetaldehyde / Q000737:chemistry; D000085:Acetates / Q000737:chemistry; D045855:Acetobacterium / Q000378:metabolism* / Q000502:physiology; D000641:Ammonia / Q000737:chemistry; D001669:Biochemical Phenomena; D001671:Biochemistry; D001673:Biodegradation, Environmental; D003903:Deuterium / Q000737:chemistry; D000431:Ethanol / Q000737:chemistry; D004983:Ethanolamines / Q000737:chemistry*; D005026:Ethylene Glycols / Q000737:chemistry; D005609:Free Radicals; D006859:Hydrogen / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical
chemical_list: D000085:Acetates; D004983:Ethanolamines; D005026:Ethylene Glycols; D005609:Free Radicals; D000431:Ethanol; D000641:Ammonia; D006859:Hydrogen; C009546:triethanolamine; D003903:Deuterium; D000079:Acetaldehyde; C005398:phenoxyethanol