Assessing Relative Cell Survival

To assess the relative survival of cells, glass beads recovered from stress treatment experiments were transferred to wells of a 24-well microtiter plate (Greiner Bio-One), with each well containing 350 μl of fresh medium and one added bead. The plates were incubated for 5 h at 24°C and 120 revolutions min⁻¹ to allow bead-adhered cells to divide into the medium. An aliquot (300 μl) of the medium, now containing cells, was transferred to a 48-well microtiter plate, and further growth was monitored during incubation at 24°C with shaking in a BioTek Powerwave XS microplate spectrophotometer and OD₆₀₀ measurement every 30 min. Resulting growth curves were used to infer back to a theoretical starting OD using multiple regression (22 (link)).