Description | The long cytoplasmic tubular structure of the T6SS system is wrapped by a sheath structure composed of two proteins, TssB and TssC. Contraction of the sheath causes the internal tube of the T6SS with associated effectors to be propelled out of the effector cell and across the membranes of bacterial or eukaryotic target cells [ , , ].TssB and TssC assemble into tubular structures with cogwheel patterns resembling the bacteriophage contractile sheath [ ]. Several structures of T6SS sheath assemblies have been solved displaying a helical assembly [, , ]. Interactions between TssB and TssC occur between the N-terminal region of TssC and the conserved a-helix of TssB []. The two proteins of the F. novicida T6SS outer sheath, IglA (TssB) and IglB (TssC), are interdigitated into a single fold similar to that of the phage sheath. The F. novicida T6SS outer sheath has a highly interlaced two-dimensional array architecture with augmented β sheets that is essential to secretory function [].Three distinct T6SS subtypes exist, T6SSi, in which most proteobacterial T6SSs are found, including V. cholerae and P. aeruginosa; T6SSii for the Francisella T6SS; and T6SSiii for Bacteroidetes systems [ ].TssB/TssC are also known as IglA/IglB and VipA/VipB.This entry represents the N-terminal domain of TssC1, a type VI secretion system sheath protein. | Name | TssC1, N-terminal |
Short Name | TssC1_N | Type | Domain |