Fig. 2. Genetic organisation of the scl gene cluster from S. sclerotialus NRRL ISP-5269 characterised in this study and schematic representation of mutants generated. (a) Gene cluster (19 782 bp) sequenced from S. sclerotialus NRRL ISP-5269. (b) Configuration of the scl gene cluster after CRISPR/Cas9-mediated targeted gene deletion within the heterologous host S. albus. The 20-bp out of frame deletion of sclM4 generated a truncated gene, represented here as a rectangular shape for the derived gene sequence. (c) Configuration of the scl cluster within S. albus double mutants; deletion of genes sclN, sclQ1-4 and sclA were generated starting from strain S. albus/scl ΔsclM4, and are represented here as dotted lines.