**AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** ESCHERICHIA COLI (E. COLI) O-ANTIGEN SEROTYPING PLAYS A VITAL ROLE IN DIAGNOSIS, EPIDEMIOLOGICAL STUDIES, OUTBREAKS INVESTIGATIONS AND PUBLIC HEALTH MONITORING. AS WHOLE GENOME SEQUENCING IS BECOMING MORE ACCESSIBLE, UNKNOWN E. COLI STRAINS THAT DO NOT MATCH THE CURRENT DESIGNATED O TYPES ARE INCREASINGLY BEING RECOGNIZED, CREATING A KNOWLEDGE GAP ON THE POSSIBLE VIRULENT THREATS THESE NEW STRAINS MAY CONTAIN. ADDITIONALLY, THERE IS A LACK OF GUIDANCE ON HOW THESE STRAINS SHOULD BE INCORPORATED INTO THE ACCEPTED NOMENCLATURE WHICH IS VITAL FOR EFFICIENT COMMUNICATION BETWEEN SCIENTISTS. IN THIS RESEARCH WE SEQUENCED A COLLECTION OF SUSPECTED NEW E. COLI STRAINS AIMING TO IDENTIFY, ANNOTATE AND COMPARE NEW O-ANTIGEN GENE CLUSTERS (O-AGCS), IDENTIFY BIOMARKER GENES TO REFINE CURRENT TECHNOLOGIES FOR O-ANTIGEN DETECTION, AND USE AN INNOVATIVE APPROACH TO CLONE O-AGCS TO ANALYZE HOW THE O-ANTIGEN INFLUENCES THE BACTERIUM'S ABILITY TO SURVIVE AND PERSIST IN THE ENVIRONMENT UNDER STRESSCONDITIONS. IDENTIFYING NEW O-AGCS, BIOMARKER GENES, AND INCORPORATING THEM INTO THE ACCEPTED NOMENCLATURE IS IMPORTANT FOR EPIDEMIOLOGICAL STUDIES AND REDUCING THE PATHOGEN DETECTION TIME IN CLINICAL CASES AND OUTBREAK INVESTIGATIONS. LASTLY, OUR INNOVATIVE O-AGCS CLONING APPROACH IS EXPECTED TO YIELD NUMEROUS ADVANCES AND CAN BE FURTHER USED BY OTHER SCIENTISTS TO STUDY OTHER O-ANTIGEN ROLES IN PATHOGENICITY