Kellermann et al 2022_Preparation for denitrification at the cusp of anoxia
Description
Supporting information to Kellermann et al, submitted to AEM June 2022; five separate files named supplemental item 1-5. Title of paper: Preparation for denitrification and phenotypic diversification at the cusp of anoxia; a purpose for N2O reductase vis a vis multiple roles of O2 Supplemental item 1 is a description and qualification of the glucose oxidase-catalase (GOX) approach used for the removal of residual oxygen in experimental vials before inoculation. In supplemental item 2, we display the gas- and flow cytometry data in the O2 spiking experiment, including the data shown in Figure 2 and 3 in the paper. In supplemental item 3, we show the gas kinetics and microscopy analyses from the N2O spiking experiment, which in the paper is summarized in Fig 4. We also show the lack of positive effect from N2O addition on Nir expression in a NosZ deficient mutant. In supplemental item 4, we describe the steps taken to estimate apparent specific growth rates in single vials and cell yield per mol electron to N-oxides. In supplemental item 5, we describe a simple experiment where nitrite reducing cultures of Paracoccus denitrificans was spiked with N2O and O2 and the subsequent rate of nitrite reduction was assessed. Movies 1-6: Red (mCherry-NirS expression) and green (FITC, growth) fluorescence in single cells captured by flow cytometry (Movie 1-4; O2-spiking experiment) or fluorescence microscopy and image analyses (Movie 5-6; N2O spiking experiment). Movie 1: vial 1.2; Movie 2: vial 1.3; Movie 3: vial 1.8; Movie 4: vial 1.9; Movie 5: vial 2.3 and 2.4; Movie 6: vial 2.7 and 2.11.