Type III secretion, needle-protein-like (IPR021123)

Short name: T3SS_needle-like

Overlapping homologous superfamilies

Family relationships


This entry represents bacterial type III secretion system needle-like proteins. Type III secretion systems are essential virulence determinants for many Gram-negative bacterial pathogens, acting to translocate proteins, usually virulence factors, out across both inner and outer membranes of bacteria and into the cytoplasm of the host cell. These proteins include:

  • Needle proteins, including MxiH, YscF, EscF, PscF, EprI, that form the needle of the injection apparatus. For instance, MxiH is an extracellular alpha helical needle that is required for translocation of effector proteins into host cells, and once inside, the effector proteins subvert normal cell function to aid infection [PMID: 16888041].
  • YscI (Yop proteins translocation protein I) in Yersinia and HrpB (hypersensitivity response and pathogenicity protein B) in plant pathogens such as Pseudomonas syringae. YscI is involved in the translocation of Yop proteins across the bacterial membrane or in the specific control of this function.

GO terms

Biological Process

GO:0009405 pathogenesis
GO:0015031 protein transport

Molecular Function

No terms assigned in this category.

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.