Fig. 4

Engineered production of chromomycins in S. roseiscleroticus. a HPLC analysis (420 nm) of chromomycins production by wild type S. roseiscleroticus (i), S. roseiscleroticus SR2 (ii, srcmRII disruption), S. roseiscleroticus SR1 (iii, srcmRI overexpression), S. roseiscleroticus SR3 (iv, srcmRI overexpression and srcmRII disruption) in R5 agar. b The disruption strategy of scrmRII in S. roseiscleroticus using a double crossover homologous recombination approach. c PCR conformation of the double crossover mutant (S. roseiscleroticus/ΔscrmRII). M: 1 kb plus DNA ladder; 1: PCR product from the mutant; 2: PCR product from the wild type