Formaldehyde metabolism by Escherichia coli. Carbon and solvent deuterium incorporation into glycerol, 1,2-propanediol, and 1,3-propanediol.
Escherichia coli were grown on 14.3% uniformly 13C-labeled glucose as the sole carbon source and challenged anaerobically with 90% 13C-labeled formaldehyde. The major multiply labeled metabolites were identified by 13C NMR spectroscopy to be glycerol and 1,2-propanediol, and a minor metabolite was shown to be 1,3-propanediol. In each case, formaldehyde is incorporated only into the C1 position. A novel form of 13C NMR isotope dilution analysis of the major products reveals that all the 1,2-diol C1 is formaldehyde derived but that about 40% of the glycerol C1 is derived from bacterial sources. Glycerokinase converted the metabolite [1-13C]glycerol to equal amounts of [3-13C]glycerol 3-phosphate and [1-13C]glycerol 3-phosphate, demonstrating that the metabolite is racemic. When [13C]formaldehyde incubation was carried out in H2O/D2O mixtures, deuterium incorporation was detected by beta- and gamma-isotope shifts. The 1,3-diol is deuterium labeled only at C2 and only once, while the 1,2-diol and glycerol are each labeled independently at both C2 and C3; C3 is multiply labeled. Deuterium incorporation levels are different for each metabolite, indicating that the biosynthetic pathways probably diverge early.
D003903:Deuterium; D004926:Escherichia coli / Q000378:metabolism*; D005557:Formaldehyde / Q000378:metabolism*; D005990:Glycerol / Q000096:biosynthesis*; D005991:Glycerol Kinase / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D019946:Propylene Glycol; D011409:Propylene Glycols / Q000378:metabolism*; D012997:Solvents
D011409:Propylene Glycols; D012997:Solvents; D005557:Formaldehyde; C041787:1,3-propanediol; D019946:Propylene Glycol; D003903:Deuterium; D005991:Glycerol Kinase; D005990:Glycerol