Undergraduate researchers at Worcester Polytechnic Institute are studying antimicrobial peptides found in fish gills with the aim of creating engineered surfaces that kill bacteria responsible for foodborne illnesses and hospital-acquired infections
Living in an environment teaming with bacteria and fungi, fish have evolved powerful defenses against waterborne pathogens, including antimicrobial peptides located in their gills. Undergraduate researchers at Worcester Polytechnic Institute (WPI) are studying the biology and the mechanics of one of those peptides with the hope they can use that knowledge to create engineered surfaces that kill bacteria responsible for foodborne illnesses and hospital-acquired infections.
The research team, led by Terri Camesano, professor of chemical engineering, reports its latest findings in the paper "Creating Antibacterial Surfaces with the Peptide Chrysophsin-1," published online in October by the journal ACS Applied Materials & Interfaces.
"Fish have a wonderful solution for blocking bacterial and fungal infections," Camesano said. "In this study, we are working to better understand the biochemical mechanics of that process."
As fish filter water through their gills to extract oxygen, antimicrobial peptides (AMPs), including Chrysosphin-1, trap and kill pathogens before they can invade the fish's bloodstream. Scientists in many laboratories around the world are actively exploring the potential use of these molecules to prevent human infections. In the current study, the WPI team attached AMPs to silicon and gold surfaces using two different approaches and measured the bound peptides' ability to kill the bacterial pathogen E. coli.
E. coli cells cultured with antimicrobial peptides (AMPs) bound to silicon crystals (the green cells are alive; the red are dead). The AMPs on the left are flat; those on the right are vertical.
In the first method, the AMPs were absorbed directly onto gold and silicon crystals, forming a single layer of molecules with the AMPs lying flat on the surface. In the second method, the tips of the AMPs were attached to the surfaces with a glue-like substance so that the peptides rose vertically, like blades of grass extending up from the ground.
Surfaces with both AMP configurations were cultured with E. coli cells. The results showed that when the AMPs were lying flat they killed 34 percent of the bacteria in the culture, but when they were standing up vertically they killed 82 percent.