FIG. 4.

Southern hybridization analysis for detection of pKB1 in total DNA of pKB1-deficient mutant Kb1-K43 and G. westfalica Kb1. The isolated total DNA of the G. westfalica Kb1 wild type and of the pKB1-deficient mutant Kb1-K43 was digested with EcoRI, separated by agarose gel electrophoresis, and stained with ethidium bromide (A), and the fragments were transferred to a nylon membrane for Southern blotting (B). The DNA of complete plasmid pKB1 was used as a digoxigenin-labeled probe. λ:PstI, λ DNA digested with PstI; WT, total DNA of G. westfalica Kb1 wild type; K43, total DNA of G. westfalica K43.