Protein Domain : POTRA domain IPR034746

Type	Domain
Description	The polypeptide-transport-associated (POTRA) domain is a module found in members of the FtsQ/DivIB, ShlB, CGI51 (with one repeat), Toc75, YTFM (withthree repeats) and D15 (with five repeats) protein families. The POTRA domains are hypothesized to mediate protein-protein interactions, nucleate beta-strands formation in nascent outer membrane proteins (OMPs) and have chaperone-like activity [, , , , ].The POTRA domain fold comprises a three-stranded β-sheet overlaid with a pair of antiparallel helices. The order of secondary-structure elements isbeta-α-α-β-β; the first and second beta strands form the two edges of the sheet, with the beta3 strand sandwiched between them. The conserved residues that define the POTRA domains areprimarily in the hydrophobic core or loop regions, suggesting that they are important for the structural integrity of POTRA domain [, , , ].Some proteins known to contain a POTRA domain are listed below:Escherichia coli outer membrane protein assembly factor BamA, involved in assembly and insertion of β-barrel proteins into the outer membrane.Escherichia coli cell division protein FtsQ.Bacillus subtilis cell division protein DivIB.Serratia marcescens hemolysin transporter protein ShlB, a virulence-factor transporter that is present in the outer membrane.Arabidopsis thaliana chloroplastic protein TOC75, mediates the insertion of proteins targeted to the outer membrane of chloroplasts.Human sorting and assembly machinery component 50 (SAM50), plays a crucial role in the maintenance of the structure of mitochondrial cristae and theproper assembly of the mitochondrial respiratory chain complexes.
Short Name	POTRA