1pbi: Difference between revisions

Revision as of 15:27, 21 February 2008

CRYSTAL STRUCTURE OF A BOWMAN-BIRK INHIBITOR FROM PEA SEEDS

OverviewOverview

The trypsin/chymotrypsin inhibitors from winter pea seeds (PsTI) are members of the Bowman-Birk protease inhibitor (BBPI) family. The crystal structure of the isoform PsTI-IVb was determined by molecular replacement at 2.7 A resolution using the X-ray co-ordinates of the soybean inhibitor as a search model. The inhibitor crystallized with a nearly perfect 2-fold symmetric dimer in the asymmetric unit. Although the overall structure is very similar to that seen in other BBPIs, there are notable new structural features. Unlike the previously reported X-ray structures of BBPIs, the structure of PsTI-IVb includes the C-terminal segment of the molecule. The C-terminal tail of each subunit is partly beta-stranded and interacts with the 2-fold symmetry-related subunit, forming a beta-sheet with strands A and B of this subunit. The dimer is mainly stabilized by a large internal hydrogen-bonded network surrounded by two hydrophobic links. Fluorescence anisotropy decay measurements show that residues Tyr59 and Tyr43 are mobile in the picosecond time scale with a large amplitude. The fluorescence study and a molecular model of the simultaneous binding of PsTI-IVb to porcine trypsin and bovine chymotrypsin are compatible only with a monomeric state of the functional molecule in solution.

About this StructureAbout this Structure

1PBI is a Single protein structure of sequence from Pisum sativum. Full crystallographic information is available from OCA.

ReferenceReference

Dimeric crystal structure of a Bowman-Birk protease inhibitor from pea seeds., Li de la Sierra I, Quillien L, Flecker P, Gueguen J, Brunie S, J Mol Biol. 1999 Jan 22;285(3):1195-207. PMID:9887273

Page seeded by OCA on Thu Feb 21 14:27:14 2008

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OCA

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-[[Image:1pbi.jpg|left|200px]]<br /><applet load="1pbi" size="450" color="white" frame="true" align="right" spinBox="true"
+[[Image:1pbi.jpg|left|200px]]<br /><applet load="1pbi" size="350" color="white" frame="true" align="right" spinBox="true"
 caption="1pbi, resolution 2.70&Aring;" />
 '''CRYSTAL STRUCTURE OF A BOWMAN-BIRK INHIBITOR FROM PEA SEEDS'''<br />
 ==Overview==
-The trypsin/chymotrypsin inhibitors from winter pea seeds (PsTI) are, members of the Bowman-Birk protease inhibitor (BBPI) family. The crystal, structure of the isoform PsTI-IVb was determined by molecular replacement, at 2.7 A resolution using the X-ray co-ordinates of the soybean inhibitor, as a search model. The inhibitor crystallized with a nearly perfect 2-fold, symmetric dimer in the asymmetric unit. Although the overall structure is, very similar to that seen in other BBPIs, there are notable new structural, features. Unlike the previously reported X-ray structures of BBPIs, the, structure of PsTI-IVb includes the C-terminal segment of the molecule. The, C-terminal tail of each subunit is partly beta-stranded and interacts with, the 2-fold symmetry-related subunit, forming a beta-sheet with strands A, and B of this subunit. The dimer is mainly stabilized by a large internal, hydrogen-bonded network surrounded by two hydrophobic links. Fluorescence, anisotropy decay measurements show that residues Tyr59 and Tyr43 are, mobile in the picosecond time scale with a large amplitude. The, fluorescence study and a molecular model of the simultaneous binding of, PsTI-IVb to porcine trypsin and bovine chymotrypsin are compatible only, with a monomeric state of the functional molecule in solution.
+The trypsin/chymotrypsin inhibitors from winter pea seeds (PsTI) are members of the Bowman-Birk protease inhibitor (BBPI) family. The crystal structure of the isoform PsTI-IVb was determined by molecular replacement at 2.7 A resolution using the X-ray co-ordinates of the soybean inhibitor as a search model. The inhibitor crystallized with a nearly perfect 2-fold symmetric dimer in the asymmetric unit. Although the overall structure is very similar to that seen in other BBPIs, there are notable new structural features. Unlike the previously reported X-ray structures of BBPIs, the structure of PsTI-IVb includes the C-terminal segment of the molecule. The C-terminal tail of each subunit is partly beta-stranded and interacts with the 2-fold symmetry-related subunit, forming a beta-sheet with strands A and B of this subunit. The dimer is mainly stabilized by a large internal hydrogen-bonded network surrounded by two hydrophobic links. Fluorescence anisotropy decay measurements show that residues Tyr59 and Tyr43 are mobile in the picosecond time scale with a large amplitude. The fluorescence study and a molecular model of the simultaneous binding of PsTI-IVb to porcine trypsin and bovine chymotrypsin are compatible only with a monomeric state of the functional molecule in solution.
 ==About this Structure==
-PBI is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Pisum_sativum Pisum sativum]. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1PBI OCA].
+PBI is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Pisum_sativum Pisum sativum]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1PBI OCA].
 ==Reference==
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 [[Category: Single protein]]
 [[Category: Brunie, S.]]
-[[Category: Sierra, I.Li.De.La.]]
+[[Category: Sierra, I Li De La.]]
 [[Category: bowman-birk inhibitor]]
 [[Category: chymotrypsin inhibitor]]
 [[Category: trypsin inhibitor]]
-''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Tue Nov 20 23:39:58 2007''
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:27:14 2008''