First images of 'superbugs' as they spread antibiotic resistance captured
4 Nov 2008, 1348 Hrs

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Washington, November 4 Scientists at the Oklahoma Medical Research Foundation have moved a step closer to finding a way to prevent the spread of dangerous antibiotic-resistant bacteria, also known as "superbugs".

Dr. Philip Silverman and Dr. Margaret Clarke, both OMRF researchers, say that they have been able to visually observe a major step in the process whereby superbugs spread antibiotic resistance in hospitals and throughout the general population.

"These 'superbugs' have become increasingly common since the widespread use of antibiotics began and they are now a serious public health menace. Now, for the first time, we can begin to see, literally, how they acquire and disseminate antibiotic resistance," said Silverman, who holds the Marjorie Nichlos Chair in Medical Research at OMRF.

Background information in a research article in the Proceedings of the National Academy of Sciences suggests that nearly 19,000 people in the United States had died last year after being infected with the virulent superbug known as methicillin-resistant Staphylococcus aureus (MRSA).

"MRSA and other antibiotic-resistant bugs are one of the greatest threats facing health care today. These infections are easily transmitted-they make their way into the body through breaks in the skin, even microscopic ones, and through nasal passages. They resist treatment with standard antibiotics, which makes them dangerous. And they are particularly threatening in hospitals, because they attack patients whose immune systems may already be compromised," said Dr. Stephen Prescott, OMRF President.

In their latest study, the researchers looked at the role that structures known as conjugative pili-slender, thread-like bacterial filaments-play in spreading antibiotic resistance.

Although such filaments are known to be crucial to the transmission of antibiotic resistance genes from one bacterium to another, Silverman and Clarke claim that they are the first research team to capture images of the process.

For their study, the researchers attached a fluorescent dye to a virus, which in turn bound specifically to the filaments on live bacteria, which allowed the behavior of the filaments to be recorded with a high-powered fluorescence microscope.

The group's efforts finally helped it capture a detailed series of images showing filament growth, attachment to other cells, and retraction to pull the cells together in preparation for genetic transfer.

"This is an important step forward in understanding how antibiotic resistance spreads," said Silverman.

The researchers said that they would continue studying the process whereby antibiotic resistance spreads, with a view to developing a better tools to combat the life-threatening phenomenon. (ANI)