Structural intrinsic disorder in a functionalized potyviral coat protein as a main viability determinant of its assembled nanoparticles.

The viability of viral-derived nanoparticles (virions and VLPs) aimed to nanobiotechnological functionalizations of the coat protein (CP) of turnip mosaic virus has been studied by means of advanced computational methodologies that include molecular dynamics. The study has allowed to model the structure of the complete CP and its functionalization with three different peptides and obtain essential structural features such as order/disorder, interactions, and electrostatic potentials of their constituent domains. The results provide for the first time a dynamic view of a complete potyvirus CP, since experimental available structures so far obtained lack N- and C-terminal segments. The relevance of disorder in the most distal N-terminal subdomain, and the interaction of the less distal N-terminal subdomain with the highly ordered CP core, stand out as crucial characteristic for a viable CP. Preserving them proved of outmost importance to obtain viable potyviral CPs presenting peptides at their N-terminus.