Figure 4.

Schematic of novel markerless cassettes generated for allelic replacement of capsule. Each cassette was spliced between the genes flanking the capsule loci, dexB (tan) and aliA (yellow). The cassettes are comprised of genes that confer sucrose sensitivity (sacB; blue), kanamycin resistance (kan, purple), streptomycin sensitivity (rpsL, red), and chlorinated phenylalanine sensitivity (pheS A315G, green). The light gray box represents the promoter from Sweet Janus and the dark gray box represents ribosome-binding site. The light-tan box represents the sequence downstream of dexB and the light-yellow box represents the sequence upstream of aliA from D39. The direction of the arrow indicates the gene orientation.