New Antibiotic May Cure and Prevent E. coli O157:H7 Infection
A new antibiotic that may cure as well as prevent infection from E. coli O157:H7 is the topic of a recent scientific study published in the journal Antimicrobial Agents and Chemotherapy. What makes this E. coli O157 antibiotic novel is that it takes advantage of a key antibacterial protein complex that some types of bacteria secrete to kill off competing bacteria. The study demonstrates that this new antibiotic delivered orally in experimental rabbits before and after bacterial exposure and infection with E. coli O157 resulted in prevention and recovery from a bacterial disease that infects approximately 73,000 people annually in the U.S.
Treating an infection from the bacterium E. coli O157 is problematical in two ways. The first way is that treatment with some antibiotics often makes the patient increasingly ill. When an antibiotic kills the bacteria, the bacteria then releases toxins that cause severe diarrhea and intestinal inflammation. Another complication is that the antibiotic may also kill off beneficial bacteria that the gut needs to maintain a healthy microbial environment.
Researchers working in collaboration with the biotech company AvidBiotics—a research facility that focuses on developing antibacterial proteins as an alternative to traditional antibiotic drugs—believe that they have found a solution to the aforementioned problems. Their solution is to take advantage of a protein complex that some strains of bacterial secrete to kill off competing bacteria within a shared environment. The protein complex is referred to as “R-type pyocins,” which basically are high molecular weight particles that have bacteria-killing abilities.
R-type pyocins are derived from a particularly nasty type of bacteria called “Pseudomonas aeruginosa” (P. aeruginosa), that according to scientists are able to infect just about anything that lives. It is a free-living, gram negative bacterium, commonly found in soil and water and is one of the few types of bacteria that are considered to be true pathogens of plants. However, P. aeruginosa is also recognized as an emerging opportunistic pathogen of humans, particularly in clinical settings as a source of antibiotic resistant, nosocomial (in hospital) infection.