The X-ray repair cross-complementing protein 1 (XRCC1) is a central scaffold protein involved in DNA single-strand break repair (SSBR), coordinating the assembly of multi-protein repair complexes. Its activity is regulated by post-translational modifications, particularly phosphorylation within intrinsically disordered regions (IDRs), although the structural consequences of these modifications remain poorly understood. In this study, an in silico approach is used to investigate the structural and electrostatic effects of a phosphomimetic mutation at residue S518. The full-length structure of human XRCC1 was predicted using AlphaFold2 via ColabFold, followed by structural and electrostatic analyses in UCSF ChimeraX. Predicted Local Distance Difference Test (pLDDT) scores revealed a heterogeneous structural profile, with well-defined folded domains and a low-confidence inter-domain linker region encompassing S518, consistent with intrinsic disorder. Introduction of the phosphomimetic mutation (S518D) did not result in substantial alterations to the global structure of XRCC1. However, electrostatic surface analysis indicated the emergence of a localized negatively charged region at the mutation site. Additional structural inspection suggested localized perturbations without global destabilization. These findings suggest that residue-level modifications at S518 may modulate the local electrostatic environment of XRCC1 and potentially influence its interactions with downstream DNA repair factors. This study highlights the role of electrostatic tuning within intrinsically disordered regions as a possible regulatory mechanism in scaffold proteins. However, as these observations are based on static computational models, further validation using molecular dynamics simulations and experimental approaches is required.