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Immunosorbent turnip vein clearing virus (TVCV) particles displaying the IgG-binding domains D and E of <i>Staphylococcus aureus</i> protein A (PA) on every coat protein (CP) subunit (TVCV_PA) were purified from plants via optimized and new protocols. The latter used polyethylene glycol (PEG) raw precipitates, from which virions were selectively re-solubilized in reverse PEG concentration gradients. This procedure improved the integrity of both TVCV_PA and the wild-type subgroup 3 tobamovirus. TVCV_PA could be loaded with more than 500 IgGs per virion, which mediated the immunocapture of fluorescent dyes, GFP, and active enzymes. Bi-enzyme ensembles of cooperating glucose oxidase and horseradish peroxidase were tethered together on the TVCV_PA carriers via a single antibody type, with one enzyme conjugated chemically to its Fc region, and the other one bound as a target, yielding synthetic multi-enzyme complexes. In microtiter plates, the TVCV_PA-displayed sugar-sensing system possessed a considerably increased reusability upon repeated testing, compared to the IgG-bound enzyme pair in the absence of the virus. A high coverage of the viral adapters was also achieved on Ta₂O₅ sensor chip surfaces coated with a polyelectrolyte interlayer, as a prerequisite for durable TVCV_PA-assisted electrochemical biosensing via modularly IgG-assembled sensor enzymes.