Summary: Coiled-coil receptor-binding R-domain of colicin E2
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Coiled-coil receptor-binding R-domain of colicin E2 Provide feedback
E2 is a DNase which utilises the outer membrane receptor BtuB to bind to and enter the cell. This family of proteins is E2R135 (residues 321-443) which is the part of E2 which is responsible for binding to BtuB in a coiled coil formation .
Sharma O, Yamashita E, Zhalnina MV, Zakharov SD, Datsenko KA, Wanner BL, Cramer WA; , J Biol Chem. 2007;282:23163-23170.: Structure of the complex of the colicin E2 R-domain and its BtuB receptor. The outer membrane colicin translocon. PUBMED:17548346 EPMC:17548346
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This tab holds annotation information from the InterPro database.
InterPro entry IPR024566
Bacteriocins are protein antibiotics that kill bacteria closely related to the producing species. Colicins are a subgroup of bacteriocins that are produced by and target Escherichia coli. The lethal action of most colicins is exerted either by formation of a pore in the cytoplasmic membrane of the target cell, or by an enzymatic nuclease digestion mechanism.
Most colicins are able to translocate the outer membrane by a two-receptor system, where one receptor is used for the initial binding and the second for translocation. The initial binding is to cell surface receptors such as the porins OmpF, FepA, BtuB, Cir and FhuA. The presence of specific periplasmic proteins, such as TolA, TolB, TolC, or TonB, are required for translocation across the membrane [PUBMED:12423783].
Colicins are composed of domains with distinct functional roles. In general they contain a central R (receptor) domain that mediates receptor binding, an N-terminal T (translocation) domain that mediates translocation of the protein from the outer membrane receptor to the colicin's target within the cell, and a C-terminal C (catalytic) domain that performs the catalytic cleavage [PUBMED:12409205].
This entry represents the central R domain found in colicin-E2 and other colicins.
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Curation and family details
|Number in seed:||2|
|Number in full:||37|
|Average length of the domain:||126.60 aa|
|Average identity of full alignment:||56 %|
|Average coverage of the sequence by the domain:||19.71 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 23193494 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||3|
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There are 5 interactions for this family. More...
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For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the E2R135 domain has been found. There are 6 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein seqence.
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