Tween 20

The lysates in Fig. 1D were prepared with the 2 × sodium dodecyl sulfate (SDS; Affymetrix/USB, J18220) buffer in the GFP-Trap^®_A protocol (ver. 2014-12-18) offered by ChromoTek (Planegg-Martinsried, Germany). The rest of the lysates were prepared with 1% (v/v or w/v) of the indicated detergents in the dilution buffer for GFP-Trap^®_A, with cOmplete^™ EDTA-free Protease Inhibitor Cocktail (Roche, 04693159001) instead of the suggested protease inhibitors. The detergents used were Tween 20 (Biosesang, T1027), Triton X-100 (Bio Basic, TB0198), Nonidet P-40 (Bio Basic, NDB0385), Octyl-β-D-glucopyranoside (Fluka, 75083), n-Dodecyl β-D-maltoside (DDM; ThermoFisher, 89903), CHAPS (Sigma-Aldrich, C5070), CHAPSO (Calbiochem, 220201), and Zwittergent 3–16 (Calbiochem, 693023). 300 μl of lysis buffer was added per tube and the tube was vortexed for 1 min to produce a homogenous mixture. The mixture was then centrifuged for 5 min at 10,000 × g at 4°C (10°C for Zwittergent 3–16- or SDS-solubilized lysates) to remove tissue debris. The intermediate supernatant was transferred to a fresh tube and centrifuged once more to obtain the final transparent tissue lysate. Total protein quantification was performed with a Pierce^™ BCA Protein Assay Kit (ThermoFisher, 23227). The final lysates were stored at −80°C.

Gold (iii) chloride trihydrate (HAuCl₄·3H₂O), polyethyleneimine (PEI, branched, MW = 800 Da), and bovine serum albumin (BSA) were purchased from Sigma Aldrich (St. Louis, MO, USA). Trisodium citrate dihydrate was obtained from BioBasic (Ontario, Canada). l-Ascorbic acid (AA) sodium salt and polyethylene glycol (PEG, MW = 8000 Da) were purchased from Alfa Aesar (Ward Hill, MA, USA). Copper chloride dihydrate (CuCl₂·2H₂O) was purchased from Junsei (Tokyo, Japan). Tris[hydroxymethyl]aminomethane (tris) was purchased from Bio-Rad (Hercules, CA, USA). Tween-20 was purchased from Biosesang (Seongnam, Korea). The NC membrane was obtained from Nupore (Ghaziabad, India). Deionized (DI) water at 18.2 MΩ cm was purified using a Milli-Q system (Millipore, Billerica, MA, USA). Five novel synthetic peptides were synthesized by peptron (Daejeon, Korea) and their information is listed in Table 1. All reagents were used without further purification.