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PDBsum entry 2ix6
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Oxidoreductase
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PDB id
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2ix6
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References listed in PDB file
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Key reference
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Title
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Controlling electron transfer in acyl-Coa oxidases and dehydrogenases: a structural view.
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Authors
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J.Mackenzie,
L.Pedersen,
S.Arent,
A.Henriksen.
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Ref.
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J Biol Chem, 2006,
281,
31012-31020.
[DOI no: ]
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PubMed id
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Abstract
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Plants produce a unique peroxisomal short chain-specific acyl-CoA oxidase (ACX4)
for beta-oxidation of lipids. The short chain-specific oxidase has little
resemblance to other peroxisomal acyl-CoA oxidases but has an approximately 30%
sequence identity to mitochondrial acyl-CoA dehydrogenases. Two biochemical
features have been linked to structural properties by comparing the structures
of short chain-specific Arabidopsis thaliana ACX4 with and without a substrate
analogue bound in the active site to known acyl-CoA oxidases and dehydrogenase
structures: (i) a solvent-accessible acyl binding pocket is not required for
oxygen reactivity, and (ii) the oligomeric state plays a role in substrate
pocket architecture but is not linked to oxygen reactivity. The structures
indicate that the acyl-CoA oxidases may encapsulate the electrons for transfer
to molecular oxygen by blocking the dehydrogenase substrate interaction site
with structural extensions. A small binding pocket observed adjoining the flavin
adenine dinucleotide N5 and C4a atoms could increase the number of productive
encounters between flavin adenine dinucleotide and O2.
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Figure 2.
FIGURE 2. The role of the N-and C-terminal tails of ACX4 in
burying the FAD cofactor. The N terminus of subunit B (green)
and the C terminus of subunit C (tan) are made transparent to
show how they enclose the FAD cofactor.
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Figure 3.
FIGURE 3. Superposition of A. thaliana ACX1 (green and
gray) and ACX4 (beige and black) dimer. The N-terminal extension
of ACX4 (red) covering the electron transfer flavoproteins
docking area of ACDs is superposable on the C terminus of ACX1
(orange).
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The above figures are
reprinted
by permission from the ASBMB:
J Biol Chem
(2006,
281,
31012-31020)
copyright 2006.
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Secondary reference #1
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Title
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Expression, Purification and crystallization of two peroxisomal acyl-Coa oxidases from arabidopsis thaliana.
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Authors
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L.Pedersen,
A.Henriksen.
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Ref.
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Acta Crystallogr D Biol Crystallogr, 2004,
60,
1125-1128.
[DOI no: ]
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PubMed id
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Figure 1.
Figure 1 Reaction catalyzed by ACX.
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The above figure is
reproduced from the cited reference
with permission from the IUCr
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Secondary reference #2
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Title
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Arabidopsis mutants in short- And medium-Chain acyl-Coa oxidase activities accumulate acyl-Coas and reveal that fatty acid beta-Oxidation is essential for embryo development.
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Authors
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E.L.Rylott,
C.A.Rogers,
A.D.Gilday,
T.Edgell,
T.R.Larson,
I.A.Graham.
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Ref.
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J Biol Chem, 2003,
278,
21370-21377.
[DOI no: ]
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PubMed id
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Figure 3.
FIG. 3. Effect of 1.5 µM 2,4-DB on wild type and acx4
seedling growth. a, 7-day-old wild type, acx4, and kat2
seedlings grown on 1.5 µM 2,4-DB. b, root length of
7-day-old wild type, acx4, and kat2 seedlings is shown. Values
are the mean ± S.E. of measurements made on three
separate batches of 25 seedlings. 20 mM sucrose was included in
the medium.
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Figure 6.
FIG. 6. Confocal images of GFP fluorescence in peroxisomes
of 4-day-old Arabidopsis seedling expressing a GFP-MFP2 fusion
construct from line A5 (40) crossed into kat2, acx3, and acx4.
a, line A5; b, kat2:GFP-MFP2; c, acx3:GFP-MFP2; d,
acx4:GFP-MFP2. Bar, 25 µm.
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The above figures are
reproduced from the cited reference
with permission from the ASBMB
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