FEBRUARY 2008 VOLUME 4 NO. 5
Faculty Developing Screening Tool to Answer Public Health Threat of Drug-resistant Bacteria
Barlow |
Meyer |
Newsam |
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Amid international concern about the public health threat of Methicillin-resistant Staphylococcus aurea bacteria (MRSA), three professors at UC Merced are developing a powerful new screening tool that could answer widespread calls for universal staph screenings before patients are admitted to hospitals.
“Universal screening is not possible right now,” said Professor Miriam Barlow of the School of Natural Sciences. “The standard means for identifying drug-resistant staph is a two-step process that requires several days. Our screening method is being developed with the aim of accomplishing a screening in six hours or less.”
Barlow is working with professors Matt Meyer of the School of Natural Sciences and Shawn Newsam of the School of Engineering to develop what they call the Microcalorimetry Microorgamism Infectious Disease Analyzer (M2IDF), a machine that measures how bacterial cells respond to heat as a way of identifying the bacteria and determining whether they are resistant to antibiotics.
During the standard two- to five-day screening period the patient is usually treated with an antibiotic that the physician can only hope will be effective. By reducing the use of ineffective antibiotics the M2IDF will reduce the spread of resistance and prolong the use of antibiotics as an effective means of infectious disease therapy.
The M2IDF measures bacterial metabolism to determine what concentrations of antibiotics are lethal to microbes. It identifies bacteria by measuring variations during heat-stimulated denaturation of cellular components.
“We’re melting the cells, the same way ice melts,” Barlow explained. “When compounds are melting, they absorb heat at different rates. Chemical differences in different strains of bacteria make them absorb different amounts of heat at different times. These differences are the basis for identifying bacteria.”
Experiments continue with a wide variety of infectious bacteria to determine the accuracy with which the M2IDF can distinguish infectious organisms and determine antibiotic susceptibility from monocultures. That will be followed by similar experiments on mixed cultures and development of a library of response profiles of an increasingly wide variety of pathogens. The project will eventually require partnering with a medical engineering and instrumentation company before a prototype high-throughput M2IDF instrument can be refined and turned into a well-designed, user-friendly, reliable instrument that can be provided at a reasonable cost to hospitals.
The growing program in biomedical research at UC Merced is a vital component of an innovative medical education program planned leading to a future medical school to begin educating doctors in Merced in 2013. For more information, please see http://med.ucmerced.edu.