title: Stable-isotope studies of glutamate catabolism in Fusobacterium nucleatum.
abstract: Catabolism of glutamate was investigated in Fusobacterium nucleatum, an anaerobic micro-organism that is strongly implicated in periodontal disease. The distribution of labels in acetate and butyrate derived from [13C]glutamates was determined by NMR spectroscopy and MS. The label from L-[5-13C]glutamate was not incorporated, whereas C-1 of acetate and butyrate were efficiently labelled by L-[1-13C]glutamate; these results indicated that the hydroxyglutarate pathway predominated. In butyrate, enrichment at C-3 was smaller than C-1; that this was not due to participation of the methylaspartate pathway was demonstrated by the incorporation of label from L-[4-13C]glutamate into only C-2 of acetate and C-4 (major)/C-2 (minor) of butyrate. The presence of label at a second site in butyrate was attributed to the synthesis of butyrate from acetate and verified by the incorporation of label from [1,2-13C2]- and [2H3]-acetate.
authors.affiliation: Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, Canada.
authors.forename: R L
authors.initials: RL
authors.lastname: White
authors.forename: M
authors.initials: M
authors.lastname: Ramezani
authors.forename: S E
authors.initials: SE
authors.lastname: Gharbia
authors.forename: R
authors.initials: R
authors.lastname: Seth
authors.forename: A L
authors.initials: AL
authors.lastname: Doherty-Kirby
authors.forename: H N
authors.initials: HN
authors.lastname: Shah
mesh_terms: D000085:Acetates / Q000378:metabolism; D002087:Butyrates / Q000378:metabolism; D002247:Carbon Isotopes; D005612:Freeze Drying; D005673:Fusobacterium / Q000378:metabolism*; D018698:Glutamic Acid / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D010510:Periodontal Diseases / Q000378:metabolism
chemical_list: D000085:Acetates; D002087:Butyrates; D002247:Carbon Isotopes; D018698:Glutamic Acid