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Fig. 2 | BMC Microbiology

Fig. 2

From: A decay effect of the growth rate associated with genome reduction in Escherichia coli

Fig. 2

Differentiated growth rates estimated by means of the optical turbidity and colony formation. a. Repressed increase of OD600 in comparison to that of CFU. The temporal changes in CFU (upper), OD600 (middle), and the ratio of the two reads (bottom) of identical population growth are shown. Error bars indicate the standard errors of the assays. b. The growth rates under varied growth conditions. Growth of the same wild-type E. coli cells growing under the different conditions (D3, D4 and Cm) was analyzed in parallel by the two methods. D3 indicates that the cell growth that started from the pre-culture reached the stationary phase with a 1000-fold dilution in fresh medium. D4 indicates that the cell growth that started from the pre-culture remained in the exponential phase with a 10,000-fold dilution in fresh medium. Cm refers to cell growth in the presence of a low concentration of antibiotics (15 μg/mL chloramphenicol). The growth rates evaluated by OD600 and CFU are indicated as μOD and μCFU, respectively. c. The growth rates of the various genotypes. The growth dynamics of E. coli cells of four reduced genomes were analyzed by the two methods in parallel. Strain Nos. 7, 14, 20 and 28 indicate multiple deletions of approximately 251, 710, 899 and 982 kbs from the wild-type genome W3110, respectively. The standard errors of the biological replication are indicated, and asterisks indicate the statistical significance (P < 0.05)

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