A 'superbug' approach to antibiotics

Dr. Keith Johnson, associate professor of biology, checks a petri dish to see if bacteria show sensitivity or resistance to a specific antibiotic. His research involves understanding the genetics that allow bacteria to build resistance to antibiotics.

By Nancy Ridgeway

Sixteen new antibiotics received FDA approval between 1983 and 1987. Twenty years later, despite the rise of antibiotic-resistant “superbugs,” only four antibiotics received FDA approval between 2003 and 2007. With the quest for new antibiotics on the decline, Bradley professors Dr. Brad Andersh and Dr. Keith Johnson hope their findings will provide a lead that will bring about a new generation of antibiotics.

Dr. Brad Andersh and Dr. Keith Johnson are modest men on a mission. Quietly working in their labs in Bradley’s Olin Hall, the two have paired their research efforts with hopes that their findings will add to the knowledge base that leads to the discovery of new antibiotics.

Such work, once done primarily by pharmaceutical companies, is now left mostly to scientists such as Dr. Andersh and Dr. Johnson. “I want to make something that has a purpose,” says Dr. Andersh, referring to his chemical research in creating compounds.

Different research, common goal

Dr. Andersh, associate professor of chemistry, and Dr. Johnson, associate professor of biology, hope that by understanding how bacteria build resistance and discovering new, effective compounds, the next generation of antibiotics will be formulated.

Dr. Johnson’s research, which he began 13 years ago, involves understanding the genetics that allow bacteria to build resistance to antibiotics. “It gets down to DNA and how it is shared between species,” he says. “The research started with mercury resistance and linked to antibiotic resistance. More recently, I have been investigating new resistance mechanisms to a relatively new antibiotic.”

Dr. Andersh, whose research on antibiotics began four years ago, has identified a new series of compounds that possess antimicrobial activity. “We identified a class of compounds that had anti-fungal activity and then found that they had antibacterial activity, as well. It’s where the science took us.”

Dr. Andersh has screened the compound against known bacteria and found it to be effective against staphylococcus, streptococcus, salmonella, E. coli, and other bacteria. He is working with strains that are not typical human pathogens.

The next step is figuring out what makes the compounds work. “Then we can look at ways to make them more effective,” Dr. Andersh says. Dr. Johnson will assist in teaching him how to handle the bacteria and how to do the testing. “We need to bring the organic chemistry back to the biology.”

Why has antibiotic research declined?

Dr. Brad Andersh, associate professor of chemistry, removes a sample from a nuclear magnetic resonance spectrometer. He has identified a new series of compounds that possess antibacterial activity and is conducting research to learn what makes the compounds work.

The increasing use of antibiotics in humans and animals has led to many bacteria developing resistance to these powerful drugs. As the bacteria evolve, the demand for new, stronger antibiotics has increased, too.

Research suggests antibiotics are over-prescribed, thus compounding the problem. “The more people use antibiotics, the faster bacteria build a resistance to the drugs,” Dr. Johnson says.

While the demand is great for new antibiotics, more research funding goes toward treating long-term diseases, which is far more profitable for pharmaceutical companies. People with diabetes, for instance, take the same drug every day for years. Antibiotics, on the other hand, are only taken for five to 10 days and often become ineffective within a few years after clinical use, as bacteria build a resistance to the drugs.

Bacteria are becoming more resistant, creating a cycle in which even stronger antibiotics are needed. An example is the rise of methicillin-resistant staphylococcus aureus (MRSA) and other hospital-based infections. The National Institute of Allergy and Infectious Diseases reports between 5 and 10 percent of all hospital patients develop an infection. About 90,000 of these patients die each year as a result of their infections.

While some small pharmaceutical and biotech companies continue to conduct antibiotic research, very little funding is channeled toward developing new antibiotics. That’s where people like Dr. Andersh and Dr. Johnson — scientists who are motivated by research that contributes to the greater good, rather than financial rewards — come in.

Realistically, Dr. Andersh and Dr. Johnson hope their findings will add to the collective pool of knowledge that will lead to a new, more effective antibiotic. Dr. Andersh says, “The chances of us developing a commercial antibiotic on our own is almost zero. But if our findings provide a lead for the ultimate development of new antibiotics, we will have benefited society by making these initial discoveries.”

Funding for this research comes from the Mund-Lagowski Department of Chemistry and Biochemistry, the Department of Biology, the University’s Special Emphasis Grant, the Bjorklund Endowed Research Fund, the Ruby K. Worner Charitable Trust, and the Frank and Faye Sherry Endowed Fund.