Doubling time using BG-11 medium with modified iron source and chelating agents

Value 4.3 hours
Organism Cyanobacteria Synechocystis PCC 6803
Reference Zavřel T et al., Quantitative insights into the cyanobacterial cell economy. Elife. 2019 Feb 4 8. pii: e42508. DOI: 10.7554/eLife.42508 p.13 bottom paragraphPubMed ID30714903
Primary Source van Alphen P et al., Increasing the Photoautotrophic Growth Rate of Synechocystis sp. PCC 6803 by Identifying the Limitations of Its Cultivation. Biotechnol J. 2018 Aug13(8):e1700764. doi: 10.1002/biot.201700764PubMed ID29577667
Method P.2 bottom paragraph: "The Synechocystis substrain GT-L (Zavřel et al., 2015b) was cultivated in flat panel photobioreactors (Figure 1A) using at least 5 independent reactors in a quasi-continuous (turbidostat) regime (Figure 1B), with red light intensities of 27.5 − 1100 μmol(photons) m^-2s^-1, supplemented with a blue light intensity of 27.5 μmol(photons) m^-2s^-1. The addition of blue light avoids possible growth limitations in the absence of short wavelength photons (Golden, 1995). Steady-state specific growth rates in turbidostat mode were calculated from monitoring the optical density measured at a wavelength of 680 nm (OD680) as well as from the rate of depletion of spare cultivation medium (as measured by top loading balances). Both methods resulted in similar average values (Figure 1C). Estimation of the specific growth rates based on the medium depletion, however, exhibited higher variance. For further analysis, therefore, only values obtained from the OD680 signal are reported."
Comments P.13 bottom paragraph: "While individual Synechocystis substrains can be more sensitive to high light (Zavřel et al., 2017), the agreement with previously reported values suggests an upper limit of Synechocystis growth in buffered BG-11 medium. However, (primary source) recently reported a specific growth rate of 0.16/h (TD=4.3h) using BG-11 medium with modified iron source and chelating agents." Primary source abstract: "Optimizing these growth conditions resulted in a so far highest growth rate of 0.16/h (4.3 h doubling time), which is significantly higher than the textbook value of 0.09 /h (8 h doubling time)."
Entered by Uri M
ID 116746