Neoplastic radiation therapy was able to alter the microbial flora of patients' bodies, as well as the microbial flora of radiationexposed workers, and provided control for possible infectious consequences. Klebsiella aerogenes was a non-fermentative aerobic gram negative bacteria that was widely distributed in nature, requiring species identification in up to 25% of cases in the lab. Antibiotic susceptibility of Klebsiella species multi-resistant isolates is common, and all isolates were characterized in all cases of clinically significant infections caused by these organisms. Only 15 isolates showed significant antimicrobial activities against at least one of the tested indicator bacteria. Vancomycin is an anti-Klebsiella species antibiotic to which resistance is rarely seen, their use should be reserved for the treatment of species infections resistant to all other antibiotics, the emergence of widespread antibiotic-resistant bacteria enhanced the need for new sources of antimicrobial isolate SHM4-1 was active against all of them, with IC60 values of 3.3 and 1.1 g/ml against HCT-116 and HepG-2 cell lines, respectively. It was genotypically identified as a species with the PKS 4 biosynthetic gene cluster present. To enhance the production, mannitol, ammonium sulphate, pH 7, 2% inoculum size, and 2 days at 37°C were utilized. This permitted separation of one active antimicrobial molecule to homogeneity using HPLC, and NMR structure elucidation revealed that this chemical was a carbapenemase derivative.