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Biology subjects

Cuccovia, I. M.

Publications and source records attributed to Cuccovia, I. M..

2 recordsLinked to original sources

Computational Design of Miniprotein Binders Targeting the Viral Entry in Chikungunya and Dengue, Neglected Tropical Diseases

Neglected Tropical Diseases (NTDs) continue to be a global health concern, affecting millions worldwide. Arboviruses such as Chikungunya virus (CHIKV) and Dengue virus (DENV) are particularly threatening due to the lack of specific antiviral treatments, the continual emergence of new variants, and their mosquito vectors. These challenges underscore the urgent need for novel antiviral strategies. Here, we apply computational methods to design miniprotein binders targeting critical viral entry components: the CHIKV envelope, and DENV fusion loop. Our protocol integrates classical and deep learning-based approaches and can be generalizable to other protein targets. Promising binder candidates were further evaluated through all-atom Molecular Dynamics simulations to assess structural stability and binding interactions. We provide complete transparency and a detailed rationale for each design step to facilitate adaptation of these protocols to other neglected disease targets. While the miniproteins presented here represent promising antiviral leads, experimental validation remains essential to confirm their biological activity.

biophysics↗

Uncovering the association mechanism between two intrinsically flexible proteins

The understanding of protein-protein interaction mechanisms is key to the atomistic description of cell signalling pathways and for the development of new drugs. In this context, the mechanism of intrinsically disordered proteins folding upon binding has attracted attention. The VirB9 C-terminal domain (VirB9Ct) and the VirB7 N-terminal motif (VirB7Nt) associate with VirB10 to form the outer membrane core complex of the Type IV Secretion System injectisome. Despite forming a stable and rigid complex, VirB7Nt behaves as a random coil while VirB9Ct is intrinsically dynamic in the free state. Here we combined NMR, stopped-flow fluorescence and computer simulations using structure-based models to characterize the VirB9Ct-VirB7Nt coupled folding and binding mechanism. Our data indicated that VirB9Ct binds to VirB7Nt by way of a conformational selection mechanism. However, at higher temperatures energy barriers between different VirB9Ct conformations are more easily surpassed. Under these conditions the formation of non-native initial encounter complexes may not be neglected, providing alternative pathways towards the native complex conformation. These observations highlight the intimate relationship between folding and binding, calling attention to the fact that the two molecular partners must search for the most favored intramolecular and intermolecular interactions on a rugged and funnelled conformational energy landscape, along which multiple intermediates may lead to the final native state.

biophysics↗