A microcosm of pathogenic bacteria resistant to antibiotics has recently developed in a particular geographical area resulting from close confinement of pathogen-carrying anii,nals from around the Nation. The investigators' laboratory routinely screens hundreds of clinical samples monthly for bacterial identification and antibiotic sensitivity.In Phase I research, recent recombinant DNA technology will be applied to "salted" nonpathogenic or clinical specimens to demonstrate feasibility of rapid, accurate, and clinically rational drug susceptibility tests.DNA probes for antibiotic resistant genes, labeled with biotin (Bioprobes) will be hybridized with microbial plasmid DNA using direct slide techniques or cellulose nitrate strips or dots to detect DNA sequences encoding resistance to ampicillin or tetracycline. Current preparatory procedures used in the laboratory will be refined to develop methods for rapid clinical specimen preparation, bacterial concentration, and Bioprobe application.Hybridized Bioprobes will be detected with rabbit antibiotin and fluorescein labeled goat antirabbit antibody or with calorimetric procedures. More rapid and clinically rational applications of visualization techniques will be investigated. This animal model may provide prototypical methodology for improved clinical diagnosis and treatment of human disease.Phase 11 research will expand Phase I technology toward commercial test "kits" for numerous resistant genes of various genera by rapid concurrent clinical procedures.Institute Of Allergy And Infectious Diseases