1cb6
From Proteopedia
(New page: 200px<br /> <applet load="1cb6" size="450" color="white" frame="true" align="right" spinBox="true" caption="1cb6, resolution 2.0Å" /> '''STRUCTURE OF HUMAN A...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:1cb6.gif|left|200px]]<br /> | + | [[Image:1cb6.gif|left|200px]]<br /><applet load="1cb6" size="350" color="white" frame="true" align="right" spinBox="true" |
| - | <applet load="1cb6" size=" | + | |
caption="1cb6, resolution 2.0Å" /> | caption="1cb6, resolution 2.0Å" /> | ||
'''STRUCTURE OF HUMAN APOLACTOFERRIN AT 2.0 A RESOLUTION.'''<br /> | '''STRUCTURE OF HUMAN APOLACTOFERRIN AT 2.0 A RESOLUTION.'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The three-dimensional structure of a form of human apolactoferrin, in | + | The three-dimensional structure of a form of human apolactoferrin, in which one lobe (the N-lobe) has an open conformation and the other lobe (the C-lobe) is closed, has been refined at 2.0 A resolution. The refinement, by restrained least-squares methods, used synchrotron radiation X-ray diffraction data combined with a lower resolution diffractometer data set. The final refined model (5346 protein atoms from residues 1-691, two Cl- ions and 363 water molecules) gives a crystallographic R factor of 0.201 (Rfree = 0. 286) for all 51305 reflections in the resolution range 10.0-2.0 A. The conformational change in the N-lobe, which opens up the binding cleft, involves a 54 degrees rotation of the N2 domain relative to the N1 domain. This also results in a small reorientation of the two lobes relative to one another with a further approximately 730 A2 of surface area being buried as the N2 domain contacts the C-lobe and the inter-lobe helix. These new contacts also involve the C-terminal helix and provide a mechanism through which the conformational and iron-binding status of the N-lobe can be signalled to the C-lobe. Surface-area calculations indicate a fine balance between open and closed forms of lactoferrin, which both have essentially the same solvent-accessible surface. Chloride ions are bound in the anion-binding sites of both lobes, emphasizing the functional significance of these sites. The closed configuration of the C-lobe, attributed in part to weak stabilization by crystal packing interactions, has important implications for lactoferrin dynamics. It shows that a stable closed structure, essentially identical to that of the iron-bound form, can be formed in the absence of iron binding. |
==Disease== | ==Disease== | ||
| Line 11: | Line 10: | ||
==About this Structure== | ==About this Structure== | ||
| - | 1CB6 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with CL as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | + | 1CB6 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with <scene name='pdbligand=CL:'>CL</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1CB6 OCA]. |
==Reference== | ==Reference== | ||
| Line 17: | Line 16: | ||
[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Anderson, B | + | [[Category: Anderson, B F.]] |
| - | [[Category: Baker, E | + | [[Category: Baker, E N.]] |
| - | [[Category: Jameson, G | + | [[Category: Jameson, G B.]] |
| - | [[Category: Norris, G | + | [[Category: Norris, G E.]] |
| - | [[Category: Thomas, D | + | [[Category: Thomas, D H.]] |
[[Category: CL]] | [[Category: CL]] | ||
[[Category: apolactoferrin]] | [[Category: apolactoferrin]] | ||
| Line 27: | Line 26: | ||
[[Category: iron transport]] | [[Category: iron transport]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:04:18 2008'' |
Revision as of 10:04, 21 February 2008
|
STRUCTURE OF HUMAN APOLACTOFERRIN AT 2.0 A RESOLUTION.
Contents |
Overview
The three-dimensional structure of a form of human apolactoferrin, in which one lobe (the N-lobe) has an open conformation and the other lobe (the C-lobe) is closed, has been refined at 2.0 A resolution. The refinement, by restrained least-squares methods, used synchrotron radiation X-ray diffraction data combined with a lower resolution diffractometer data set. The final refined model (5346 protein atoms from residues 1-691, two Cl- ions and 363 water molecules) gives a crystallographic R factor of 0.201 (Rfree = 0. 286) for all 51305 reflections in the resolution range 10.0-2.0 A. The conformational change in the N-lobe, which opens up the binding cleft, involves a 54 degrees rotation of the N2 domain relative to the N1 domain. This also results in a small reorientation of the two lobes relative to one another with a further approximately 730 A2 of surface area being buried as the N2 domain contacts the C-lobe and the inter-lobe helix. These new contacts also involve the C-terminal helix and provide a mechanism through which the conformational and iron-binding status of the N-lobe can be signalled to the C-lobe. Surface-area calculations indicate a fine balance between open and closed forms of lactoferrin, which both have essentially the same solvent-accessible surface. Chloride ions are bound in the anion-binding sites of both lobes, emphasizing the functional significance of these sites. The closed configuration of the C-lobe, attributed in part to weak stabilization by crystal packing interactions, has important implications for lactoferrin dynamics. It shows that a stable closed structure, essentially identical to that of the iron-bound form, can be formed in the absence of iron binding.
Disease
Known disease associated with this structure: Deafness, autosomal dominant 1 OMIM:[602121]
About this Structure
1CB6 is a Single protein structure of sequence from Homo sapiens with as ligand. Full crystallographic information is available from OCA.
Reference
Structure of human apolactoferrin at 2.0 A resolution. Refinement and analysis of ligand-induced conformational change., Jameson GB, Anderson BF, Norris GE, Thomas DH, Baker EN, Acta Crystallogr D Biol Crystallogr. 1998 Nov 1;54(Pt 6 Pt 2):1319-35. PMID:10089508
Page seeded by OCA on Thu Feb 21 12:04:18 2008
