Scientists warn that without changing our course, multiple antibiotic resistant bacterial infections could become “catastrophic” by the year 2050. The National Institutes of Health awarded a $1.8 million grant to Joseph Boll, whose research seeks a solution to the problem. Boll, an assistant professor at the University of Texas at Arlington, looks to research the defense mechanisms of Acinetobacter baumannii, a common bacteria in hospitals.
The bacterial species A. baumannii causes infections throughout the human body – in wounds, blood, the respiratory system and urinary tract. Of course, under normal circumstances, these infections are treated with antibiotics. Unfortunately however, many strains of the bacteria are resistant to antibiotics. This includes the carbapenems, strong antibiotics used in many cases of antibiotic resistant bacteria.
“In previous research, we discovered that when A. baumannii experiences stress, such as antibiotic treatment, it modifies its cell envelope to tolerate the antibiotic for extended periods of time,” said Professor Boll.
“Specific modifications allow the bacteria to survive long enough to acquire true antibiotic resistance, which can lead to antibiotic treatment failure. This can happen within 24 hours of antibiotic exposure.”
Professor Boll’s team has been looking at how enzymes can modify the cell envelope, allowing antibiotic resistance to develop. So far the researchers have found that two LD-transpeptidase enzymes change the cell envelope allowing the bacteria to survive long enough to develop true antibiotic resistance.
Research student Hannah Bovermann is using this information to delve into the genetics governing the LD-transpeptidase enzymes and what environmental stressors cause their activation. Looking at different factors, including temperature and pH that cause the change in the cell envelope from the enzymes, allows the scientists to understand how the antibiotic resistance develops.
“Each response brings us closer to an understanding of how cell envelope modifications keep the bacterial cell intact in stress,” said Bovermann.
“It has become a game. Researchers discover a new antimicrobial, then bacteria become resistant to it. We are running out of options,” said Professor Boll. “Bacterial resistance is quickly outpacing new antibiotic development.”