Amylose resin

All restriction enzymes, DNA-modifying enzymes, and DNA ladders were obtained from New England Biolabs. Plasmid pETM-41 and TEV protease were kindly provided by Dr Amit Sharma (ICGEB, New Delhi). Protein markers were obtained from Thermo Fisher Scientific (USA). nicotinamide Adenine Dinucleotide [Adenylate-³²P] (800Ci/mmol) was purchased from American Radiolabeled Chemicals (USA). Ni²⁺-NTA agarose and amylose resin were purchased from Qiagen and New England Biolabs, respectively. Sirtinol, nicotinamide, cambinol, and Ex-527 were obtained from Sigma-Aldrich (USA). SIRT1 Fluorometric Drug Discovery Kit and SIRT5 Fluorometric Drug Discovery Kit were procured from Enzo Life Sciences (USA). Other materials used in this study were of analytical grade and were commercially available.

The expression vector pMAL-c2x was purchased from Novagen Inc. (Darmstadt, Germany). E. coli JM109 was used as the host for plasmid construction and molecular cloning of the candidate gene. E. coli BL21 (DE3) was used as the host for heterologous expression of the candidate gene. Both of them were obtained from Invitrogen Inc. (Carlsbad, USA) and grown at 37 °C in Luria-Bertani (LB) medium (10 g L⁻¹ tryptone; 5 g L⁻¹ yeast extract; 10 g L⁻¹ NaCl and 15 g L⁻¹ agar; pH 7.0). Restriction enzymes and T4 DNA ligase were purchased from Takara Inc. (Dalian, China) and used with the provided buffer according to supplier's recommendations. QIAprep Spin MiniPrep Kit and amylose resin were purchased from Qiagen Inc. (Hilden, Germany). Aβ42 gene was codon-optimized and synthesized by GENEWIZ Inc. (Suzhou, China). Primers and sequence analyses of the constructions were performed by BGI Inc. (Shenzhen, China). Commercial Aβ42 (>95%) was purchased from GL Biochem Ltd. (Shanghai, China) Dulbecco's modified Eagle's medium and fetal bovine serum were purchased from Gibco Invitrogen Inc. (Grand Island, NY, USA). The PC12 cell line was obtained from National Infrastructure of Cell Line Resources of China. Unless noted, all other reagents and chemicals were of the highest purity available from local sources.