Figure 2. In vivo ¹³C-NMR spectra of [2−¹³C]acetate metabolism and unlabelled glucose by resting cells of Z. bailii, in aerobic conditions.

[2-¹³C]acetate (83 mM) and unlabelled glucose (63 mM) were added to a cell suspension (4–5 mg dry weight ml^-1). ¹³C-NMR spectra (2.5 min each) were acquired sequentially. An expansion of (A) in the spectral region 25–120 ppm is shown in (B). Symbols: Act-C₂ is [2–¹³C]acetate; Glu-C₂, C₃ and C₄ are the resonances due to carbon atoms 2, 3, and 4, respectively, in glutamate; Glc-C₁ (α,β) are the resonances due to carbon 1 in the two anomers of glucose (natural abundance).