A divergon is a regulon comprised of two adjacent divergent operons or genes. [More information is available at EcoGene: EG12890]. In Escherichia coli, gspD is a member of an operon of genes (gspC-O) which are not normally expressed but are homologous to those encoding the secreton, or type II secretion machinery in Klebsiella oxytoca and Aeromonase hydrophila, among others.