The nucleoid protein HU positively regulates the expression of type VI secretion systems in Enterobacter cloacae

Abstract

T6SS is a nanomachine that functions as a weapon of bacterial destruction crucial for successful colonization in a specific niche. Enterobacter cloacae expresses two T6SSs required for bacterial competition, adherence, biofilm formation, and intestinal colonization. Expression of T6SS genes in pathogenic bacteria is controlled by multiple regulatory systems, including two-component systems, global regulators, and nucleoid proteins. Here, we reported that the HU nucleoid protein directly activates both T6SSs in E. cloacae , affecting the T6SS-related phenotypes. Our data describe HU as a new regulator involved in the transcriptional regulation of T6SS and its impact on E. cloacae pathogenesis.