Figure 2.

Physiological response of Colwellia hornerae under Ceres regolith conditions when supplied with organic substrates: dodecane (a,e,i,m), isobutyronitrile (b,f,j,n), dioctyl-sulphide (c,g,k,o), and controls (d,h,l,p). (a–d) Proportion of CTC-positive (i.e., metabolically active) cells over time: (e–h) ATP production (mM cell⁻¹), (i–l) NADPH/NADP⁺ ratio, and (m–p) total protein concentration (pg cell⁻¹). Blue lines represent 1 wt% treatment (in aliphatic substrates) and no growth substrate (negative control). Red lines represent 20 wt% treatment (in aliphatic substrates) and MMB (positive control). Error bars represent standard error of the mean.