1qac: Difference between revisions

Revision as of 15:37, 21 February 2008

CHANGE IN DIMERIZATION MODE BY REMOVAL OF A SINGLE UNSATISFIED POLAR RESIDUE

OverviewOverview

The importance of unsatisfied hydrogen bonding potential on protein-protein interaction was studied. Two alternate modes of dimerization (conventional and flipped form) of an immunoglobulin light chain variable domain (V(L)) were previously identified. In the flipped form, interface residue Gln89 would have an unsatisfied hydrogen bonding potential. Removal of this Gln should render the flipped dimer as the more favorable quaternary form. High resolution crystallographic studies of the Q89A and Q89L mutants show, as we predicted, that these proteins indeed form flipped dimers with very similar interfaces. A small cavity is present in the Q89A mutant that is reflected in the approximately 100 times lower association constant than found for the Q89L mutant. The association constant of Q89A and Q89L proteins (4 x 10(6) M(-1) and >10(8) M(-1)) are 10- and 1,000-fold higher than that of the wild-type protein that forms conventional dimers clearly showing the energetic reasons for the flipped dimer formation.

About this StructureAbout this Structure

1QAC is a Protein complex structure of sequences from Homo sapiens. Full crystallographic information is available from OCA.

ReferenceReference

Change in dimerization mode by removal of a single unsatisfied polar residue located at the interface., Pokkuluri PR, Cai X, Johnson G, Stevens FJ, Schiffer M, Protein Sci. 2000 Sep;9(9):1852-5. PMID:11045631

Page seeded by OCA on Thu Feb 21 14:37:36 2008

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA

@@ Line 1: / Line 1: @@
-[[Image:1qac.gif|left|200px]]<br /><applet load="1qac" size="450" color="white" frame="true" align="right" spinBox="true"
+[[Image:1qac.gif|left|200px]]<br /><applet load="1qac" size="350" color="white" frame="true" align="right" spinBox="true"
 caption="1qac, resolution 1.80&Aring;" />
 '''CHANGE IN DIMERIZATION MODE BY REMOVAL OF A SINGLE UNSATISFIED POLAR RESIDUE'''<br />
 ==Overview==
-The importance of unsatisfied hydrogen bonding potential on, protein-protein interaction was studied. Two alternate modes of, dimerization (conventional and flipped form) of an immunoglobulin light, chain variable domain (V(L)) were previously identified. In the flipped, form, interface residue Gln89 would have an unsatisfied hydrogen bonding, potential. Removal of this Gln should render the flipped dimer as the more, favorable quaternary form. High resolution crystallographic studies of the, Q89A and Q89L mutants show, as we predicted, that these proteins indeed, form flipped dimers with very similar interfaces. A small cavity is, present in the Q89A mutant that is reflected in the approximately 100, times lower association constant than found for the Q89L mutant. The, association constant of Q89A and Q89L proteins (4 x 10(6) M(-1) and &gt;10(8), M(-1)) are 10- and 1,000-fold higher than that of the wild-type protein, that forms conventional dimers clearly showing the energetic reasons for, the flipped dimer formation.
+The importance of unsatisfied hydrogen bonding potential on protein-protein interaction was studied. Two alternate modes of dimerization (conventional and flipped form) of an immunoglobulin light chain variable domain (V(L)) were previously identified. In the flipped form, interface residue Gln89 would have an unsatisfied hydrogen bonding potential. Removal of this Gln should render the flipped dimer as the more favorable quaternary form. High resolution crystallographic studies of the Q89A and Q89L mutants show, as we predicted, that these proteins indeed form flipped dimers with very similar interfaces. A small cavity is present in the Q89A mutant that is reflected in the approximately 100 times lower association constant than found for the Q89L mutant. The association constant of Q89A and Q89L proteins (4 x 10(6) M(-1) and &gt;10(8) M(-1)) are 10- and 1,000-fold higher than that of the wild-type protein that forms conventional dimers clearly showing the energetic reasons for the flipped dimer formation.
 ==About this Structure==
-QAC is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1QAC OCA].
+QAC is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1QAC OCA].
 ==Reference==
@@ Line 15: / Line 15: @@
 [[Category: Cai, X.]]
 [[Category: Johnson, G.]]
-[[Category: Pokkuluri, P.R.]]
+[[Category: Pokkuluri, P R.]]
 [[Category: Schiffer, M.]]
-[[Category: Stevens, F.J.]]
+[[Category: Stevens, F J.]]
 [[Category: beta barrel immunoglobulin vl domain dimer]]
 [[Category: flipped domain dimer]]
-''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Wed Nov 21 00:31:27 2007''
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:37:36 2008''