Fig. 5
Construction and characterization of AATPL1-knockout strains. a PCR detection of a bleHH insertion into crRNA target sites. M: molecular size markers (λ-EcoT14 I digest), PCR product amplified with DNA from W: strain NIES-2152, CR12: strain CR12, CR97: strain CR97, and N: no DNA. b The target sequences of AATPL1_1- and AATPL1_3 crRNAs and the corresponding sequences in the knockout strains, CR12 and CR7. Each 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. At one side of the cleavage site generated by AATPL1_1 crRNA, an 8-bp deletion (Δ8) plus a 36-bp insertion (ins36) occurred. c, d Cells of the wild-type strain, strain PK4, and AATPL1-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). 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