Enzymatically active fibrils generated by the self-assembly of the ApoA-I fibrillogenic domain functionalized with a catalytic moiety

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• 作者：Fulvio Guglielmi ; Daria M. Monti ; Angela Arciello ; Silvia Torrassa ; Flora Cozzolino ; Piero Pucci ; Annalisa Relini ; Renata Piccoli
• 关键词：Self-assembly ; Bioactivity ; Apolipoprotein ; Nanobiomaterials ; Functionalized amyloid fibrils ; Catalytic fibrils
• 刊名：Biomaterials
• 出版年：2009
• 出版时间：February 2009
• 年：2009
• 卷：30
• 期：5
• 页码：829-835
• 全文大小：514 K

文摘

Enzymatically active fibrils were produced by self-assembly of a bifunctional chimeric protein, made up of a fibrillogenic and a catalytic moiety. For this purpose, the fibrillogenic domain of Apolipoprotein A-I (ApoA-I), a 93-residue polypeptide named [1-93]ApoA-I, was functionalized with the enzyme glutathione S-transferase (GST). The fusion protein GST-[1-93]ApoA-I was expressed, isolated to homogeneity and characterized. In the soluble form, GST-[1-93]ApoA-I was found to be fully active as a GST enzyme, and to have high propensity to self-aggregate. Upon incubation for 3 weeks at pH 6.4, insoluble aggregates were generated. Analyzed by AFM, they were found to contain fibrillar structures often organized into large fiber networks. Fibrils were loaded on the membrane of a microfiltration unit and tested for enzymatic activity by filtering the substrate through the fibrillar network. Fibrils were shown to be catalytically active, stable over time and reusable, as no loss of activity was detected when fibrils were repeatedly tested. Our findings suggest that catalytically active fibrils may be of interest for biocatalytic applications in nanobiotechnology.