| Method |
p.405 bottom paragraph:"Cultures of Synechococcus sp. WH 8102 and Prochlorococcus spp. MED 4 and MIT 9313 obtained from the Provasoli-Guillard National Center for Marine Algae and Microbiota were grown at 22–23 °C with innoculation in a 1:4 dilution into PCR S11 and Pro99 media. Cultures were grown under 20–40 µmol photons m^-2·s^-1 on a 12:12 light:dark cycle. Culture growth was tracked by daily absorbance measures of 1 mL culture sub-samples (UV-1800 Shimadzu spectrophotometer, Shimadzu, Kyoto, Japan and UVProbe software, version 1.1). Absorbance at 750 nm (A750) was subtracted from the absorbance at 680 nm (A680) to obtain a scattering-corrected chlorophyll content approximation. These cultures achieved a stable apparent quantum yield of photosynthesis of 0.4 (Synechococcus) or 0.6 (Prochlorococcus) determined by the ratio of the variable fluorescence (FV) to the maximum fluorescence (FM) using a Xenon-PAM fluorometer (Walz, Effeltrich, Germany). Exponential growth rates were estimated by measuring the slope of the linear portion of the logarithmic growth curve. Samples for subsequent protein and functional analyses were harvested after 48–72 h of exponential growth." |