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1rh1
From Proteopedia
(New page: 200px<br /><applet load="1rh1" size="450" color="white" frame="true" align="right" spinBox="true" caption="1rh1, resolution 2.5Å" /> '''crystal structure of ...) |
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| - | [[Image:1rh1.gif|left|200px]]<br /><applet load="1rh1" size=" | + | [[Image:1rh1.gif|left|200px]]<br /><applet load="1rh1" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1rh1, resolution 2.5Å" /> | caption="1rh1, resolution 2.5Å" /> | ||
'''crystal structure of the cytotoxic bacterial protein colicin B at 2.5 A resolution'''<br /> | '''crystal structure of the cytotoxic bacterial protein colicin B at 2.5 A resolution'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Colicin B (55 kDa) is a cytotoxic protein that recognizes the outer | + | Colicin B (55 kDa) is a cytotoxic protein that recognizes the outer membrane transporter, FepA, as a receptor and, after gaining access to the cytoplasmic membranes of sensitive Escherichia coli cells, forms a pore that depletes the electrochemical potential of the membrane and ultimately results in cell death. To begin to understand the series of dynamic conformational changes that must occur as colicin B translocates from outer membrane to cytoplasmic membrane, we report here the crystal structure of colicin B at 2.5 A resolution. The crystal belongs to the space group C2221 with unit cell dimensions a = 132.162 A, b = 138.167 A, c = 106.16 A. The overall structure of colicin B is dumbbell shaped. Unlike colicin Ia, the only other TonB-dependent colicin crystallized to date, colicin B does not have clearly structurally delineated receptor-binding and translocation domains. Instead, the unique N-terminal lobe of the dumbbell contains both domains and consists of a large (290 residues), mostly beta-stranded structure with two short alpha-helices. This is followed by a single long ( approximately 74 A) helix that connects the N-terminal domain to the C-terminal pore-forming domain, which is composed of 10 alpha-helices arranged in a bundle-type structure, similar to the pore-forming domains of other colicins. The TonB box sequence at the N-terminus folds back to interact with the N-terminal lobe of the dumbbell and leaves the flanking sequences highly disordered. Comparison of sequences among many colicins has allowed the identification of a putative receptor-binding domain. |
==About this Structure== | ==About this Structure== | ||
| - | 1RH1 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http:// | + | 1RH1 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1RH1 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Chen, G.]] | [[Category: Chen, G.]] | ||
| - | [[Category: Hilsenbeck, J | + | [[Category: Hilsenbeck, J L.]] |
[[Category: Kang, C.]] | [[Category: Kang, C.]] | ||
[[Category: Park, H.]] | [[Category: Park, H.]] | ||
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[[Category: tonb]] | [[Category: tonb]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:50:49 2008'' |
Revision as of 12:50, 21 February 2008
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crystal structure of the cytotoxic bacterial protein colicin B at 2.5 A resolution
Overview
Colicin B (55 kDa) is a cytotoxic protein that recognizes the outer membrane transporter, FepA, as a receptor and, after gaining access to the cytoplasmic membranes of sensitive Escherichia coli cells, forms a pore that depletes the electrochemical potential of the membrane and ultimately results in cell death. To begin to understand the series of dynamic conformational changes that must occur as colicin B translocates from outer membrane to cytoplasmic membrane, we report here the crystal structure of colicin B at 2.5 A resolution. The crystal belongs to the space group C2221 with unit cell dimensions a = 132.162 A, b = 138.167 A, c = 106.16 A. The overall structure of colicin B is dumbbell shaped. Unlike colicin Ia, the only other TonB-dependent colicin crystallized to date, colicin B does not have clearly structurally delineated receptor-binding and translocation domains. Instead, the unique N-terminal lobe of the dumbbell contains both domains and consists of a large (290 residues), mostly beta-stranded structure with two short alpha-helices. This is followed by a single long ( approximately 74 A) helix that connects the N-terminal domain to the C-terminal pore-forming domain, which is composed of 10 alpha-helices arranged in a bundle-type structure, similar to the pore-forming domains of other colicins. The TonB box sequence at the N-terminus folds back to interact with the N-terminal lobe of the dumbbell and leaves the flanking sequences highly disordered. Comparison of sequences among many colicins has allowed the identification of a putative receptor-binding domain.
About this Structure
1RH1 is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Crystal structure of the cytotoxic bacterial protein colicin B at 2.5 A resolution., Hilsenbeck JL, Park H, Chen G, Youn B, Postle K, Kang C, Mol Microbiol. 2004 Feb;51(3):711-20. PMID:14731273
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