3bf0
From Proteopedia
(New page: 200px<br /><applet load="3bf0" size="350" color="white" frame="true" align="right" spinBox="true" caption="3bf0, resolution 2.550Å" /> '''Crystal structure o...) |
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caption="3bf0, resolution 2.550Å" /> | caption="3bf0, resolution 2.550Å" /> | ||
'''Crystal structure of Escherichia coli Signal peptide peptidase (SppA), Native crystals'''<br /> | '''Crystal structure of Escherichia coli Signal peptide peptidase (SppA), Native crystals'''<br /> | ||
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| + | ==Overview== | ||
| + | Signal peptide peptidase (Spp) is the enzyme responsible for cleaving the remnant signal peptides left behind in the membrane following Sec-dependent protein secretion. Spp activity appears to be present in all cell types, eukaryotic, prokaryotic and archaeal. Here we report the first structure of a signal peptide peptidase, that of the Escherichia coli SppA (SppA(EC)). SppA(EC) forms a tetrameric assembly with a novel bowl-shaped architecture. The bowl has a dramatically hydrophobic interior and contains four separate active sites that utilize a Ser/Lys catalytic dyad mechanism. Our structural analysis of SppA reveals that while in many Gram-negative bacteria as well as characterized plant variants, a tandem duplication in the protein fold creates an intact active site at the interface between the repeated domains, other species, particularly Gram-positive and archaeal organisms, encode half-size, unduplicated SppA variants that could form similar oligomers to their duplicated counterparts, but using an octamer arrangement and with the catalytic residues provided by neighboring monomers. The structure reveals a similarity in the protein fold between the domains in the periplasmic Ser/Lys protease SppA and the monomers seen in the cytoplasmic Ser/His/Asp protease ClpP. We propose that SppA may, in addition to its role in signal peptide hydrolysis, have a role in the quality assurance of periplasmic and membrane-bound proteins, similar to the role that ClpP plays for cytoplasmic proteins. | ||
==About this Structure== | ==About this Structure== | ||
3BF0 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=3BF0 OCA]. | 3BF0 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=3BF0 OCA]. | ||
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| + | ==Reference== | ||
| + | Crystal structure of a bacterial signal Peptide peptidase., Kim AC, Oliver DC, Paetzel M, J Mol Biol. 2008 Feb 15;376(2):352-66. Epub 2007 Dec 4. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=18164727 18164727] | ||
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
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[[Category: transmembrane]] | [[Category: transmembrane]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 19:05:18 2008'' |
Revision as of 17:05, 21 February 2008
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Crystal structure of Escherichia coli Signal peptide peptidase (SppA), Native crystals
Overview
Signal peptide peptidase (Spp) is the enzyme responsible for cleaving the remnant signal peptides left behind in the membrane following Sec-dependent protein secretion. Spp activity appears to be present in all cell types, eukaryotic, prokaryotic and archaeal. Here we report the first structure of a signal peptide peptidase, that of the Escherichia coli SppA (SppA(EC)). SppA(EC) forms a tetrameric assembly with a novel bowl-shaped architecture. The bowl has a dramatically hydrophobic interior and contains four separate active sites that utilize a Ser/Lys catalytic dyad mechanism. Our structural analysis of SppA reveals that while in many Gram-negative bacteria as well as characterized plant variants, a tandem duplication in the protein fold creates an intact active site at the interface between the repeated domains, other species, particularly Gram-positive and archaeal organisms, encode half-size, unduplicated SppA variants that could form similar oligomers to their duplicated counterparts, but using an octamer arrangement and with the catalytic residues provided by neighboring monomers. The structure reveals a similarity in the protein fold between the domains in the periplasmic Ser/Lys protease SppA and the monomers seen in the cytoplasmic Ser/His/Asp protease ClpP. We propose that SppA may, in addition to its role in signal peptide hydrolysis, have a role in the quality assurance of periplasmic and membrane-bound proteins, similar to the role that ClpP plays for cytoplasmic proteins.
About this Structure
3BF0 is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Crystal structure of a bacterial signal Peptide peptidase., Kim AC, Oliver DC, Paetzel M, J Mol Biol. 2008 Feb 15;376(2):352-66. Epub 2007 Dec 4. PMID:18164727
Page seeded by OCA on Thu Feb 21 19:05:18 2008
