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Updated: Jul 18, 2025

Selection of Aptamers for Amyloid β-Protein, the Causative Agent of Alzheimer's Disease
Published on: May 13, 2010
Discovering the deep evolutionary roots of serum amyloid A protein family
Marcel Zámocký1, Peter Ferianc2
1Laboratory of Phylogenomic Ecology, Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, SK-84551 Bratislava, Slovakia; Department of Inorganic Chemistry, Faculty of Natural Sciences, Comenius University Bratislava, Mlynská dolina, Ilkovičova 6, SK-84215 Bratislava, Slovakia.
Abstract:
Deep evolutionary origin of the conserved animal serum amyloid A (SAA) apolipoprotein family leading to yet unknown highly similar SAA-like sequences occurring in certain bacterial genomes is demonstrated in this contribution. Horizontal gene transfer event of corresponding genes between gut bacteria and non-vertebrate animals was discovered in the reconstructed phylogenetic tree obtained with maximum likelihood and neighbor-joining methods, respectively. This detailed phylogeny based on totally 128 complete sequences comprised diverse serum amyloid A isoforms from various animal vertebrate and non-vertebrate phyla and also corresponding genes coding for highly similar proteins from animal gut bacteria. Typical largely conserved sequence motifs and a peculiar structural fold consisting mainly of four α-helices in a bundle within all reconstructed clades of the SAA protein family are discussed with respect to their supposed biological functions in various organisms that contain corresponding genes.
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