Analysis of suppressor mutations of spoIVCA mutations: Occurrence of DNA rearrangement in the absence of a site-specific DNA recombinase SpoIVCA in Bacillus subtilis

The spoIVCA gene of Bacillus subtilis encodes a site-specific recombinase, which excises a 38-kb skin element from the chromosomal DNA by DNA rearrangement and creates a new composite gene, sigK, on the chromosome. From spoIVCA mutants, we have isolated Spo(+) revertants which have no skin element but have an intact sigK gene. This result suggests that the DNA rearrapgement can occur in the absence of spoIVCA.