Extended Data Fig. 10: Regulation of nitrogenase activity in the E. coli MG1655 ‘Marionette’ strain.
From: Control of nitrogen fixation in bacteria that associate with cereals
(a) Controller plasmids used to drive expression of T7 promoters. (b) Inducibility of the T7 promoter by the controller plasmids encoding T7 RNAP under the regulation of the 12 sensors was tested with a reporter plasmid pMR123 (right). (c) Inducible control of nitrogenase activity in response to 12 inducers was tested with each of 12 controller plasmid and the plasmid pMR138 (right) carrying the refactored nif cluster v2.1 on pBBR1 origin. The choline-Cl inducible system was omitted for activity assay as the system was not inducible. For the DAPG-, DHBA-, and vanillic acid-inducible system, the refactored cluster v2.1 was carried on a lower copy number plasmid pMR31 (right) as there was no colony formation from the transformation of the plasmid pMR138. The inducer concentrations are: 400 μM arabinose, 1 mM choline-Cl, 500 nM 3OC14HSL, 50 μM cuminic acid, 25 nM 3OC6HSL, 25 μM DAPG, 500 μM DHBA, 1 mM IPTG, 100 nM aTc, 250 μM naringenin, 50 μM vanillic acid, and 250 μM salicylic acid. Plasmid and genetic parts are provided in Supplementary Table 3 and 4. Error bars represent standard deviation from three independent experiments on different days.
