The post-translational incorporation of arginine into a beta-amyloid peptide increases the probability of alpha-helix formation.
The beta-amyloid peptide (beta AP1-40) inhibited the in vitro post-translational incorporation of [14C]arginine at the N-terminus of brain soluble proteins and was labelled by the incorporation of [14C]arginine. Addition of arginine at the N-terminal position of beta AP1-40 is predicted to increase the probability of an alpha-helix structure being formed on the first residues with a higher hydrophilic characteristic, increasing the possibility of these residues being exposed to the aqueous environment. Unmodified beta AP1-40 has a low alpha-helix content and a higher probability of beta-turn formation. Accumulation of beta AP1-40 in Alzheimer's disease may therefore be due to a reduced arginylation reaction and consequently to a decrease in its normal degradation by the ubiquitin pathway.
Bongiovanni
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G
Dpto. Química Biológica, Universidad Nacional de Córdoba, Argentina.
Fidelio
G D
GD
Barra
H S
HS
Hallak
M E
ME
D016229:Amyloid beta-Peptides / Q000737:chemistry / Q000378:metabolism*; D001120:Arginine / Q000737:chemistry*; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism*; D011336:Probability; D011499:Protein Processing, Post-Translational; D017433:Protein Structure, Secondary
D016229:Amyloid beta-Peptides; D010446:Peptide Fragments; C078592:amyloid beta-protein (1-40); D001120:Arginine