2026-11-122026-11-122026BENJAMIN, João Vitor dos Santos. Análise in silico da propensão antigênica do ectodomínio da proteína de fusão dos vírus ilhéus e rocio. Orientador: Carlos Alberto Marques de Carvalho. 2026. 92 f. Dissertação (Mestrado em Biologia Parasitária na Amazônia) - Centro de Ciências Biológicas e da Saúde, Universidade do Estado do Pará, Belém, 2026.https://portaldaposgraduacao.uepa.br/handle/riuepa/451AbertoMicrobiologiaEpidemiológaProteína viral-fusãoMicrobiologyEpidemiologyViral fusion proteinDissertaçãoCiências BiológicasCiências Biológicas::MicrobiologiaCiências Biológicas::Microbiologia::Biologia e Fisiologia dos MicroorganismosIn the Amazon, the high diversity of arboviruses and vectors makes epidemiological control difficult, with Brazil being particularly vulnerable due to its entomological and environmental diversity. Ilhéus (ILHV) and Rocio (ROCV) viruses belong to the same species (Orthoflavivirus ilheusense), circulating in multiple hosts and with serological evidence in several Brazilian regions, including recent severe human cases. The persistence and geographic expansion of these flaviviruses reinforce the need for continuous surveillance, improved diagnosis, and understanding of transmission dynamics to prevent new outbreaks. This study aimed to analyze in silico the antigenic propensity of the ectodomain of the E protein of ILHV and ROCV. Initially, the ectodomain region of the E protein was defined and reference sequences (RefSeq) were obtained from the GenBank database. Subsequently, the following steps were performed: alignment using the Needle server; obtaining molecular weight, net charge, isoelectric point, and residual polarities using the PEPSTATS tool; Prediction of secondary structures using the PREDATOR tool; identification of post-translational modification sites using the NetPhos 3.1 and NetNglyc tools; modeling with the PHYRE2.2 server; refinement with the MODREFINER server; analysis of the quality of three-dimensional structures with the PROCHECK server; evaluation of antigenicity with the PCPROF tool; and estimation of the peptide's binding affinity to HLA-I/II molecules with the NetMHCpan-4.1, NetMHCIIpan-4.0, and Epitope Evaluator servers. The alignment showed high identity and similarity, but with some specific differences. Residual polarities showed a predominance of apolar profiles in all sequences. On the other hand, there was a greater presence of beta sheets than alpha helices in the polypeptide chains. For post-translational modifications, a greater number of consensus patterns were observed for serine (S), threonine (T), and tyrosine (Y) phosphorylation than for asparagine (N) glycosylation. Modeling of the three-dimensional structures revealed distinctions in domain II of the E protein among the viruses. Antigenic propensity showed a distribution in both the N terminal and C-terminal regions. Finally, the HLA-1 alleles HLA.B39.01, HLA.B15.01, HLA.A01.01, and HLA.A26.01, and the HLA-II alleles DRB3.02.02, DRB4.01.01, DRB1.03.01, and DRB4.01.01 stood out in the recognition of ectodomain peptides of the E protein. Therefore, differences were observed that may influence functionality, immune response, and disease progression, serving as a basis for elucidating potential therapeutic andPPG-BPA - Morfofisiologia e genética dos agentes infecciosos, parasitários e vetores de endemias na Amazônia