Figure 2: Optimization of in vivo hydrocarbon production from CO reduction.
From: The in vivo hydrocarbon formation by vanadium nitrogenase follows a secondary metabolic pathway
(a) Hydrocarbon formation by 250 ml cultures of A. vinelandii strains carrying encoding genes for V (,)- and Mo ()-nitrogenases on incubation with various CO concentrations for 8 h. CO was added on depletion of ammonia without (,) or with () supplementation of additional ammonia to the growth media. (b) Specific yield of in vivo hydrocarbon formation by V-nitrogenase upon incubation with various CO concentrations for 8 h. (c) Linear increases of C2H4 (left), C2H6 (middle) and C3H8 (right) formation by a 250 ml culture of the V-nitrogenase-expressing A. vinelandii strain every 4 h on repeated addition of CO with intermittent 20 min aeration. A 250 ml culture expressing the V-nitrogenase yielded 14,981 nmol C2H4, 626 nmol C2H6 and 71 nmol C3H8, respectively, after 20 cycles of repeated addition of 2.6 mmol CO in a 250 ml gas phase with intermittent aeration, which was equivalent to 1.2% carbon conversion. Data of activity analysis were obtained from three independent experiments (n=6) and presented as mean±s.d.
