Flagellar L-ring protein (IPR000527)

Short name: Flag_Lring

Overlapping homologous superfamilies


Family relationships



The flgH, flgI and fliF genes of Salmonella typhimurium encode the major proteins for the L, P and M rings of the flagellar basal body [PMID: 2544561]. In fact, the basal body consists of four rings (L,P,S and M) surrounding the flagellar rod, which is believed to transmit motor rotation to the filament [PMID: 2129540]. The M ring is integral to the inner membrane of the cell, and may be connected to the rod via the S (supramembrane) ring, which lies just distal to it. The L and P rings reside in the outer membrane and periplasmic space, respectively. FlgH and FlgI, which are exported across the cell membrane to their destinations in the outer membrane and periplasmic space, have typical N-terminal cleaved signal-peptide sequences. FlgH is predicted to have an extensive beta-sheet structure, in keeping with other outer membrane proteins [PMID: 2544561].

GO terms

Biological Process

GO:0071973 bacterial-type flagellum-dependent cell motility

Molecular Function

GO:0003774 motor activity

Cellular Component

GO:0009427 bacterial-type flagellum basal body, distal rod, L ring

Contributing signatures

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