Figure 5.

TMV equipment with biotin linkers and [SA]-enzymes. A: Scheme of TMV functionalization. A coupling-competent TMV variant (TMV_Cys, yellow) was coated with bifunctional maleimide-PEG₁₁-biotin linkers resulting in TMV_Cys/Bio (green), followed by affinity binding of [SA]-enzymes (purple). B: Selective linker coupling to CP_Cys (17.6 kDa) was possible with ca. 50% efficiency, as shown by specific gel shift of the CP_Cys band (CP_Bio). Molecular weight marker bands as indicated (15% SDS-PAGE stained with Coomassie Brilliant Blue R250). C: Transmission electron microscopy of TMV_Cys/Bio particles before and after binding of [SA]-enzymes (mix of [SA]-GOx:[SA]-HRP 14:1). The enzymes form a fluffy seam with protrusions, distributed over the whole particle length. Samples were adsorbed on Formvar^®-coated carbon-sputtered copper grids and negatively stained with 2% uranyl acetate; bars: 100 nm. Images show data obtained according to reference [132].