@misc{10481/99704, year = {2024}, month = {8}, url = {https://hdl.handle.net/10481/99704}, abstract = {The ubiquitin E2 variant domain of TSG101 (TSG101-UEV) plays a pivotal role in protein sorting and virus budding by recognizing PTAP motifs within ubiquitinated proteins. Disrupting TSG101-UEV/PTAP interactions has emerged as a promising strategy for the development of novel host-oriented antivirals with a broad spectrum of action. Nonetheless, finding inhibitors with good properties as therapeutic agents remains a challenge since the key determinants of binding affinity and specificity are still poorly understood. Here we present a detailed thermodynamic, structural, and dynamic characterization viral PTAP Late domain recognition by TSG101-UEV, combining isothermal titration calorimetry, X-ray diffraction structural studies, molecular dynamics simulations, and computational analysis of intramolecular communication pathways. Our analysis highlights key contribu- tions from conserved hydrophobic contacts and water-mediated hydrogen bonds at the PTAP binding interface. We have identified additional electrostatic hotspots adjacent to the core motif that modulate affinity. Using competitive phage display screening we have improved affinity by 1–2 orders of magnitude, producing novel peptides with low micromolar affinities that combine critical elements found in the best natural binders. Mo- lecular dynamics simulations revealed that optimized peptides engage new pockets on the UEV domain surface. This study provides a comprehensive view of the molecular forces directing TSG101-UEV recognition of PTAP motifs, revealing that binding is governed by conserved structural elements yet tuneable through targeted optimization. These insights open new venues to design inhibitors targeting TSG101-dependent pathways with potential application as novel broad-spectrum antivirals.}, organization = {This work was supported by the MCIN/AEI/10.13039/ 501100011033/and FEDER Una manera de hacer Europa [grant numbers BIO2016-78746-C2-1-R, PID2020-112895RB-I00]; the FEDER/Junta de Andalucía-Consejería de Economía y Conocimiento [grant number CV20-19149]; and the Consejería de Universidad, Investigaci´on e Innovaci´on and FEDER Andalusian Program 2021-2027 [grant number C-EXP-295-UGR23].}, publisher = {Elsevier}, keywords = {Virus budding}, keywords = {Broad-spectrum antivirals}, keywords = {TSG101 UEV domain}, keywords = {Viral Late domains}, keywords = {Polyproline recognition domains}, title = {Phage display identification of high-affinity ligands for human TSG101-UEV: A structural and thermodynamic study of PTAP recognition}, doi = {https://doi.org/10.1016/J.IJBIOMAC.2024.133233}, author = {Murciano Calles, Javier and Rodríguez-Martínez, Alejandro and Palencia, Andrés and Andújar-Sánchez, Montserrat and Iglesias Bexiga, Manuel and Corbi Verge, Carles and Buzón, Pedro and Ruiz Sanz, Javier and Martínez Herrerías, José Cristóbal and Perez Sanchez, Horacio and Cámara-Artigas, Ana and Luque Fernández, Irene}, }