Sandbox Reserved 702: Difference between revisions
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The edema factor has a 30 kDa protective antigen-binding domain at its <scene name='Sandbox_Reserved_702/Coloration_from_n_to_c_term/1'>N-terminus.</scene> (shown in blue) | The edema factor has a 30 kDa protective antigen-binding domain at its <scene name='Sandbox_Reserved_702/Coloration_from_n_to_c_term/1'>N-terminus.</scene> (shown in blue) | ||
This domain exposes a richly negative-charged surface which easily interacts with the positively charged residues of the protective antigen. Edema factor's protective antigen-binding domain can be divided into two subdomains. The N-terminal domain is composed of three layers, α/β sandwich domain (four β-sheets β1 to β4, in sandwich between four α-helices α1 to α4). The C-terminal domain is composed of five helices. The protective antigen-binding domain contains five joining loops L1 to L5, and L5 has the key exposed residues that bind to the protective antigen. Residues in α6, α7 and in the joining loop between α7 and α8 at the C-terminal domain are also implied in the interaction. <ref> PMID: 15719022</ref> | This domain exposes a richly negative-charged surface which easily interacts with the positively charged residues of the protective antigen. Edema factor's protective antigen-binding domain can be divided into two subdomains. The N-terminal domain is composed of three layers, α/β sandwich domain (four β-sheets β1 to β4, in sandwich between four α-helices α1 to α4). The C-terminal domain is composed of five helices. <scene name='Sandbox_Reserved_702/Secondary_structure/1'>See the secondary structure.</scene> {{Template:ColorKey_Helix}}, | ||
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The protective antigen-binding domain contains five joining loops L1 to L5, and L5 has the key exposed residues that bind to the protective antigen. Residues in α6, α7 and in the joining loop between α7 and α8 at the C-terminal domain are also implied in the interaction. <ref> PMID: 15719022</ref> | |||
The edema factor is delivered into host cells thanks to the protective antigen. Indeed, the protective antigen binds to cellular receptors (CMP2, capillary morphogenesis protein 2 or TEM8, tumor endothelial marker 8) and is cleaved at the sequence arginine-lysine-lysine-arginine by cell surface proteases. This proteolytic activation leads to the oligomerisation of a protective antigen heptamer. The heptamer is composed of the C-terminal 63 kDa fragment. One heptamer can bind three molecules of edema factor (or lethal factor). Such a complex gets into the cell by endocytosis and finally the protective antigen helps the translocation of the edema factor from late endosome into the cytoplasm. Once it is in the host cell, the edema factor becomes membrane-associated. It is not known whether it is due to its association with [[calmodulin]] or to its binding with other cellular elements. <ref> PMID: 19560485</ref> | The edema factor is delivered into host cells thanks to the protective antigen. Indeed, the protective antigen binds to cellular receptors (CMP2, capillary morphogenesis protein 2 or TEM8, tumor endothelial marker 8) and is cleaved at the sequence arginine-lysine-lysine-arginine by cell surface proteases. This proteolytic activation leads to the oligomerisation of a protective antigen heptamer. The heptamer is composed of the C-terminal 63 kDa fragment. One heptamer can bind three molecules of edema factor (or lethal factor). Such a complex gets into the cell by endocytosis and finally the protective antigen helps the translocation of the edema factor from late endosome into the cytoplasm. Once it is in the host cell, the edema factor becomes membrane-associated. It is not known whether it is due to its association with [[calmodulin]] or to its binding with other cellular elements. <ref> PMID: 19560485</ref> | ||
