Fig. 4
Construction and characterization of DMAN1-knockout strains. a PCR detection of a bleHH insertion. The primer set DMAN1_F and DMAN1_R2 (Additional file 7: Table S1) was used to detect bleHH insertion into a crRNA target site. M: molecular size markers (λ-EcoT14 I digest), PCR product amplified with DNA from W: strain NIES-2152, CR189: strain CR189, CR193: strain CR193, and N: no DNA. b The target sequence of DMAN1_2 crRNA and the corresponding sequences in the knockout strains, CR189 and CR193. Each of broad orange arrow represents one unit length of bleHH. A Δ symbol followed by a number indicates a deletion of base(s) with this number at one end of bleHH. Inserted nucleotide(s) are shown in red. c, d Cells of the wild-type strain, strain PK4, and CDMT1-knockout strains were grown in 1/5 UP medium under continuous light for 4–14 days. c Volumetric biomass yield [cell mass dry weight per liter of culture (g l−1)]. d Lipid content in percentage of dry weight biomass (w/w). Bars represent standard deviations of data from three independent samples. Statistical significance of differences between the values of strain PK4 and those of other strains were tested by Student’s t test (two-tailed), and the results are shown as asterisks. Single asterisks indicate P values between 0.01 and 0.05, and double asterisks indicate P < 0.01