1p6p
From Proteopedia
(New page: 200px<br /><applet load="1p6p" size="450" color="white" frame="true" align="right" spinBox="true" caption="1p6p, resolution 2.5Å" /> '''Crystal Structure of ...) |
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| - | [[Image:1p6p.jpg|left|200px]]<br /><applet load="1p6p" size=" | + | [[Image:1p6p.jpg|left|200px]]<br /><applet load="1p6p" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1p6p, resolution 2.5Å" /> | caption="1p6p, resolution 2.5Å" /> | ||
'''Crystal Structure of Toad Liver Basic Fatty Acid-Binding Protein'''<br /> | '''Crystal Structure of Toad Liver Basic Fatty Acid-Binding Protein'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Two paralogous groups of fatty acid-binding proteins (FABPs) have been | + | Two paralogous groups of fatty acid-binding proteins (FABPs) have been described in vertebrate liver: liver FABP (L-FABP) type, extensively characterized in mammals, and liver basic FABP (Lb-FABP) found in fish, amphibians, reptiles, and birds. We describe here the toad Lb-FABP complete amino acid sequence, its X-ray structure to 2.5 A resolution, ligand-binding properties, and mechanism of fatty acid transfer to phospholipid membranes. Alignment of the amino acid sequence of toad Lb-FABP with known L-FABPs and Lb-FABPs shows that it is more closely related to the other Lb-FABPs. Toad Lb-FABP conserves the 12 characteristic residues present in all Lb-FABPs and absent in L-FABPs and presents the canonical fold characteristic of all the members of this protein family. Eight out of the 12 conserved residues point to the lipid-binding cavity of the molecule. In contrast, most of the 25 L-FABP conserved residues are in clusters on the surface of the molecule. The helix-turn-helix motif shows both a negative and positive electrostatic potential surface as in rat L-FABP, and in contrast with the other FABP types. The mechanism of anthroyloxy-labeled fatty acids transfer from Lb-FABP to phospholipid membranes occurs by a diffusion-mediated process, as previously shown for L-FABP, but the rate of transfer is 1 order of magnitude faster. Toad Lb-FABP can bind two cis-parinaric acid molecules but only one trans-parinaric acid molecule while L-FABP binds two molecules of both parinaric acid isomers. Although toad Lb-FABP shares with L-FABP a broad ligand-binding specificity, the relative affinity is different. |
==About this Structure== | ==About this Structure== | ||
| - | 1P6P is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bufo_arenarum Bufo arenarum]. Full crystallographic information is available from [http:// | + | 1P6P is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bufo_arenarum Bufo arenarum]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1P6P OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Corsico, B.]] | [[Category: Corsico, B.]] | ||
| - | [[Category: Monaco, H | + | [[Category: Monaco, H L.]] |
[[Category: Perduca, M.]] | [[Category: Perduca, M.]] | ||
| - | [[Category: Pietro, S | + | [[Category: Pietro, S M.Di.]] |
| - | [[Category: Santome, J | + | [[Category: Santome, J A.]] |
[[Category: beta barrel]] | [[Category: beta barrel]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:25:47 2008'' |
Revision as of 12:25, 21 February 2008
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Crystal Structure of Toad Liver Basic Fatty Acid-Binding Protein
Overview
Two paralogous groups of fatty acid-binding proteins (FABPs) have been described in vertebrate liver: liver FABP (L-FABP) type, extensively characterized in mammals, and liver basic FABP (Lb-FABP) found in fish, amphibians, reptiles, and birds. We describe here the toad Lb-FABP complete amino acid sequence, its X-ray structure to 2.5 A resolution, ligand-binding properties, and mechanism of fatty acid transfer to phospholipid membranes. Alignment of the amino acid sequence of toad Lb-FABP with known L-FABPs and Lb-FABPs shows that it is more closely related to the other Lb-FABPs. Toad Lb-FABP conserves the 12 characteristic residues present in all Lb-FABPs and absent in L-FABPs and presents the canonical fold characteristic of all the members of this protein family. Eight out of the 12 conserved residues point to the lipid-binding cavity of the molecule. In contrast, most of the 25 L-FABP conserved residues are in clusters on the surface of the molecule. The helix-turn-helix motif shows both a negative and positive electrostatic potential surface as in rat L-FABP, and in contrast with the other FABP types. The mechanism of anthroyloxy-labeled fatty acids transfer from Lb-FABP to phospholipid membranes occurs by a diffusion-mediated process, as previously shown for L-FABP, but the rate of transfer is 1 order of magnitude faster. Toad Lb-FABP can bind two cis-parinaric acid molecules but only one trans-parinaric acid molecule while L-FABP binds two molecules of both parinaric acid isomers. Although toad Lb-FABP shares with L-FABP a broad ligand-binding specificity, the relative affinity is different.
About this Structure
1P6P is a Single protein structure of sequence from Bufo arenarum. Full crystallographic information is available from OCA.
Reference
Structural and biochemical characterization of toad liver fatty acid-binding protein., Di Pietro SM, Corsico B, Perduca M, Monaco HL, Santome JA, Biochemistry. 2003 Jul 15;42(27):8192-203. PMID:12846568
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