Escherichia coli is a Gram-negative commensal of human gut. Surprisingly, the role of E. coli in the pathogenesis of ulcerative colitis (UC) has not been explored till date. Human gut microbiota composition and meta-gut resistome was evaluated using metagenomics. Antibiotic susceptibility of E. coli isolates against different class of antibiotics was investigated. Further, the genome sequence analysis of E. coli isolates was performed to get insight into the antimicrobial resistance (AMR) mechanism and virulence factors. Gut proteome of UC and non-UC was examined to understand the effect of resistant bacteria on host physiology. In UC patients, meta-gut resistome was found to be dominated by AMR genes (829) compared to healthy control (HC) [518]. Metagenome study revealed higher prevalence of AMR genes in rural population (378 in HC; 607 in UC) compared to urban (340 in HC; 578 in UC). Approximately, 40% of all E. coli isolates were multi-drug resistant with higher prevalence in UC (43.75%) compared to HC (33.33%). Up-regulated expression of antimicrobial human proteins (lactotransferrin, azurocidin, cathepsin G, neutrophil elastase, and neutrophil defensin 3) and immuneproteins (Protein S100-A9 and Protein S100-A8) suggest microbial infection in UC gut. In addition to the conventional culturomics method, multi-omics strategy provides deeper insights into the disease etiology, emergence of pathobionts, andits role in the disruption of the healthy gut environment in UC patients.