Fig. 2: Development of the genetic engineering method for S. cellulosum.

a Biosynthesis of carotenoids in S. cellulosum So ce10. b Construction of the pXZ-crtBKO plasmid and possible outcomes from homologous recombination. c Verification of crtB disruption by phenotype (i) and genotype (ii). The colour of the numbers above the gel lanes indicates the colony appearance: orange numbers indicate colonies with an orange phenotype, and black numbers indicate colonies with a white phenotype. A total of 42 white colonies from three independent biological replicates (N = 3) were validated by genotype, uncropped gels are provided in the Source data file. d Optimisation of the electroporation conditions. Error bars represent mean ± SD. N = 3 biological replicates for each temperature condition; N = 4, 3, 4, 5 replicates for OD₆₀₀ of 0.5, 1, 1.5, 2, respectively; N = 5, 4, 4, 5 replicates for Voltage of 12, 15, 18, 21 kV/cm, respectively; N = 5, 10, 5, 9, 5 replicates for pulse number of 1, 2, 3, 4, 5, respectively. e, f Impact of homology arm length on overall transformation efficiency and ratio of double-crossover events. Error bars represent mean ± SD, N = 4 biological replicates. g Disruption of the crtB gene in S. cellulosum So ce307 and So ce836. Statistical analysis was performed using two-tailed Student’s t test or one-way ANOVA followed by Tukey’s multiple comparisons test (***p   <   0.001; ****p   <   0.0001). Source data are provided as a Source data file.