Combating ESKAPE Pathogens Through the Discovery of Novel Antimicrobial Molecules

Abstract

According to the CDC, there are more than 2.8 million antibiotic resistant infections occurring in the United States each year, and more than 35,000 people die as a result (CDC 2019). Furthermore, the CDC classifies a group of bacteria known as ESKAPE pathogens as six emerging antibiotic-resistant pathogens that are difficult to eradicate with current antibiotics. Our study aims to discover and investigate microorganisms that have the potential to produce antimicrobial molecules that inhibit ESKAPE pathogens. We hypothesize that we will be able to identify bacteria from the soil that inhibit the growth of the following nosocomial associated safe relatives of Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, or Enterobacter species (ESKAPE). To test our hypothesis, we collected soil samples from Fayetteville State University (FSU) campus and serially diluted samples onto LB agar plates. Next, 63 unique colonies were obtained from the agar plates and screened against non-pathogenic ESKAPE safe relatives. After analysis, 12 of the FSU soil isolates (FSI) resulted in a zone of clearance indicating that it was able to produce an antimicrobial agent against the safe relatives. MacConkey agar plates were used to test metabolism and cell wall structure, motility tested, the presence of the enzyme catalase was analyzed, and lastly the soil isolates were tested for antibiotic susceptibility. Collectively, one isolate was Gram-positive, eleven Gram-negative, and all but one of the soil isolates were shown to be catalase positive. All FSI’s were resistant to the antibiotic penicillin. In conclusion, these results support our hypothesis that we can identify soil bacteria that produce antimicrobial peptides that inhibit the growth of safe relative ESKAPE pathogens. We hope this study leads to the identification of novel antimicrobial producing microorganisms that can inhibit the spread of antibiotic resistant ESKAPE bacteria.