Contrasted Reactivity to Oxygen Tensions in Frankia sp. Strain CcI3 throughout Nitrogen Fixation and Assimilation

Figure 2

Relative gene expression (fold change) in response to hyperoxic and hypoxic conditions. Frankia cultures were grown under nitrogen-replete (NH₄) or nitrogen-deficient (N₂) conditions. These cultures were exposed to oxic (N), hyperoxic (H), and hypoxic (L) conditions as described in Section 2. Experimental gene expression was normalized to the rpsA housekeeping gene and compared to the calibrator (NH₄ oxic conditions). The following genes were analyzed: (a) nifHDK (b) gltB and gltD, (c) glnA genes, (d) hpnC and sqhC, (e) hup1 and hup2, (f) hboN and hboO, and (g) sodA and katA.

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