Type VI secretion systems (T6SS) allow bacteria to inject effector proteins into neighboring cells. While these systems can target a wide range of cell types, they require direct contact with their target cells. Although attachment is therefore essential for the successful injection of effectors, the coordination of secretion and attachment remains poorly understood. The single T6SS of Yersinia enterocolitica is encoded across two neighboring operons, both of which harbor genes for type I fimbriae. While the system is inactive under standard laboratory conditions, it is activated by a single nucleotide polymorphism in the histidine kinase of a two-component system. Beyond the integrated T6SS/T1F system, this strain displays strong upregulation of other attachment systems and a concurrent drastic downregulation of flagella and chemotaxis, indicating a switch from a motile, planktonic lifestyle to an adherent, secretion-active state. Transmission electron and fluorescence microscopy revealed increased pilus production and a dense arrangement of T6SS structures. Proteomics analyses enabled us to delineate the regulons involved in this lifestyle switch and to identify a T6SS effector nuclease. Given that the genetic arrangement is conserved in various pathogenic bacteria, the integration of T6SS and fimbrial attachment systems and the genetic switch described herein may be a common feature allowing bacteria to adapt to changing conditions.

Children with cystic fibrosis (CF) commonly harbor Staphylococcus aureus thymidine-dependent small-colony variants (TD-SCVs), which are associated with reduced lung function and increased respiratory ...

While Staphylococcus aureus is predominantly an extracellular human commensal, it can also exhibit an intracellular lifestyle that enables its persistence within diverse host cell types, including mon...

A synthetic cell can now grow and divide—but it’s still far from alive

-

Research has revealed how bacteria rely on circadian clocks to control the spread of their multi-cellular colonies…

The database of 200 million protein-structure predictions now includes homodimers, adding new biological relevance.

PhD Project - Image-based bacterial phenotyping and antimicrobial drug discovery using smart high-throughput super-resolution microscopy at University of Warwick, listed on FindAPhD.com