FIG. 2.

Generation of Pru ΔSAG2CDXY strain. The figures shows a schematic of the SAG2C locus in type II strains. The four closely related genes SAG2C, -D, -X, and -Y are tandemly located on chromosome X. Gene identification numbers (Toxodb release 4.2) are given in parentheses. The premature stop codon in the SAG2D gene is indicated, and introns are shown as shaded boxes. The map is not drawn to scale. Double homologous recombination between the SAG2CDXY knockout construct and genomic DNA replaces SAG2CDXY with the HPT gene, which was used for positive selection.