1by6: Difference between revisions

From Proteopedia
Jump to navigation Jump to search
No edit summary
No edit summary
Line 4: Line 4:


==Overview==
==Overview==
We have studied the three-dimensional structure of a biologically active, peptide of apolipoprotein C-II (apoC-II) in the presence of lipid mimetics, by CD and NMR spectroscopy. This peptide, corresponding to residues 44-79, of apoC-II, has been shown to reverse the symptoms of genetic apoC-II, deficiency in a human subject. A comparison of alpha-proton secondary, shifts and CD spectroscopic data indicates that the structure of, apoC-II(44-79) is similar in the presence of dodecylphosphocholine and, sodium dodecyl sulfate. The three-dimensional structure of apoC-II(44-79), in the presence of sodium dodecyl sulfate, determined by relaxation matrix, calculations, contains two amphipathic helical domains formed by residues, 50-58 and 67-75, separated by a non-helical linker centered at Tyr63. The, C-terminal helix is terminated by a loop formed by residues 76-79. The, C-terminal helix is better defined and has a larger hydrophobic face than, the N-terminal helix, which leads us to propose that the C-terminal helix, together with the non-helical Ile66 constitute the primary lipid binding, domain of apoC-II(44-79). Based on our structure we suggest a new, mechanism of lipoprotein lipase activation in which both helices of, apoC-II(44-79) remain lipid bound, while the seven-residue interhelical, linker extends away from the lipid surface in order to project Tyr63 into, the apoC-II binding site of lipoprotein lipase.
We have studied the three-dimensional structure of a biologically active peptide of apolipoprotein C-II (apoC-II) in the presence of lipid mimetics by CD and NMR spectroscopy. This peptide, corresponding to residues 44-79 of apoC-II, has been shown to reverse the symptoms of genetic apoC-II deficiency in a human subject. A comparison of alpha-proton secondary shifts and CD spectroscopic data indicates that the structure of apoC-II(44-79) is similar in the presence of dodecylphosphocholine and sodium dodecyl sulfate. The three-dimensional structure of apoC-II(44-79) in the presence of sodium dodecyl sulfate, determined by relaxation matrix calculations, contains two amphipathic helical domains formed by residues 50-58 and 67-75, separated by a non-helical linker centered at Tyr63. The C-terminal helix is terminated by a loop formed by residues 76-79. The C-terminal helix is better defined and has a larger hydrophobic face than the N-terminal helix, which leads us to propose that the C-terminal helix together with the non-helical Ile66 constitute the primary lipid binding domain of apoC-II(44-79). Based on our structure we suggest a new mechanism of lipoprotein lipase activation in which both helices of apoC-II(44-79) remain lipid bound, while the seven-residue interhelical linker extends away from the lipid surface in order to project Tyr63 into the apoC-II binding site of lipoprotein lipase.


==Disease==
==Disease==
Line 15: Line 15:
Structure of a biologically active fragment of human serum apolipoprotein C-II in the presence of sodium dodecyl sulfate and dodecylphosphocholine., Storjohann R, Rozek A, Sparrow JT, Cushley RJ, Biochim Biophys Acta. 2000 Jul 19;1486(2-3):253-64. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=10903476 10903476]
Structure of a biologically active fragment of human serum apolipoprotein C-II in the presence of sodium dodecyl sulfate and dodecylphosphocholine., Storjohann R, Rozek A, Sparrow JT, Cushley RJ, Biochim Biophys Acta. 2000 Jul 19;1486(2-3):253-64. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=10903476 10903476]
[[Category: Single protein]]
[[Category: Single protein]]
[[Category: Cushley, R.J.]]
[[Category: Cushley, R J.]]
[[Category: Rozek, A.]]
[[Category: Rozek, A.]]
[[Category: Sparrow, J.T.]]
[[Category: Sparrow, J T.]]
[[Category: Storjohann, R.]]
[[Category: Storjohann, R.]]
[[Category: amphipathic helix]]
[[Category: amphipathic helix]]
Line 24: Line 24:
[[Category: lpl activation]]
[[Category: lpl activation]]


''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri Feb 15 15:33:36 2008''
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:00:20 2008''

Revision as of 13:00, 21 February 2008

File:1by6.jpg


1by6

Drag the structure with the mouse to rotate

PEPTIDE OF HUMAN APOLIPOPROTEIN C-II

OverviewOverview

We have studied the three-dimensional structure of a biologically active peptide of apolipoprotein C-II (apoC-II) in the presence of lipid mimetics by CD and NMR spectroscopy. This peptide, corresponding to residues 44-79 of apoC-II, has been shown to reverse the symptoms of genetic apoC-II deficiency in a human subject. A comparison of alpha-proton secondary shifts and CD spectroscopic data indicates that the structure of apoC-II(44-79) is similar in the presence of dodecylphosphocholine and sodium dodecyl sulfate. The three-dimensional structure of apoC-II(44-79) in the presence of sodium dodecyl sulfate, determined by relaxation matrix calculations, contains two amphipathic helical domains formed by residues 50-58 and 67-75, separated by a non-helical linker centered at Tyr63. The C-terminal helix is terminated by a loop formed by residues 76-79. The C-terminal helix is better defined and has a larger hydrophobic face than the N-terminal helix, which leads us to propose that the C-terminal helix together with the non-helical Ile66 constitute the primary lipid binding domain of apoC-II(44-79). Based on our structure we suggest a new mechanism of lipoprotein lipase activation in which both helices of apoC-II(44-79) remain lipid bound, while the seven-residue interhelical linker extends away from the lipid surface in order to project Tyr63 into the apoC-II binding site of lipoprotein lipase.

DiseaseDisease

Known disease associated with this structure: Hyperlipoproteinemia, type Ib OMIM:[608083]

About this StructureAbout this Structure

1BY6 is a Single protein structure of sequence from [1]. Full crystallographic information is available from OCA.

ReferenceReference

Structure of a biologically active fragment of human serum apolipoprotein C-II in the presence of sodium dodecyl sulfate and dodecylphosphocholine., Storjohann R, Rozek A, Sparrow JT, Cushley RJ, Biochim Biophys Acta. 2000 Jul 19;1486(2-3):253-64. PMID:10903476

Page seeded by OCA on Thu Feb 21 12:00:20 2008

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

OCA