The E. coli minicell locus was shown to code for three gene products (MinC, MinD, and MinE) whose coordinate action is required for proper placement of the division septum. The minE gene codes for a topological specificity factor that, in wild-type cells, prevents the division inhibitor from acting at internal division sites while permitting it to block septation at polar sites [1].

1: A division inhibitor and a topological specificity factor coded for by the minicell locus determine proper placement of the division septum in E. coli. de Boer PA, Crossley RE, Rothfield LI; Cell 1989;56:641-649. PMID:2645057