Cavitt uses summer grant funds to 'gross out' bacteria
Kasie Corley |
At Lipscomb University, as knowledge grows in use it also grows in value, even on summer break. Each year, the university awards five full grants to deserving faculty members to conduct research and scholarship during the summer.
In the past, grants have resulted in the development of new courses, writing of books and poetry, innovative research in chemistry and biology, and programs to enhance Lipscomb’s reputation and relationship globally.
T. Brian Cavitt, associate professor from the Department of Chemistry & Biochemistry in the College of Liberal Arts & Sciences, focused his summer on methods to inhibit growth of microbes with his work, “Bacteria are tacky, but not for long…” Cavitt’s goal through his research is to develop a biofilm resistant coating to prevent the adhesion of harmful (i.e., bad) bacteria to surfaces while allowing beneficial (i.e., good) bacteria to remain, creating widespread benefits in its implementation.
Imagine a world in which humankind is not “grossed out” by bad bacteria rather, we make the bad bacteria go, “Ew...” Cavitt’s work can make this possible through his research into bacterial adhesins, surface energies and biofilms to produce compounds which, when added to materials like paint, clothing, sealants and many more possibilities, bacteria will not propagate due to the inhospitable environment created by the compounds.
“I can measure the surface energy of a substrate, or whatever coating I have,” Cavitt explained. “I can compare two coatings where one is made of a biofilm resistant paint and the other of a bacterial adhesin. I can measure a contact angle (see inset) with multiple solvents, and then use a mathematical model to pull out all of the data I need to determine the surface free energy of each coating. If the relationship between those two surface free energies is appropriate, the adhesin won’t want to stick to the other. The interaction is unfavorable,” he said.
“If the interaction is unfavorable, the bacteria will just tumble onto the next surface. It’s kind of cool,” said Cavitt.
?Cavitt has the ability to build a massive database in which the unfavorable metrics of all existing bacteria, both good and bad, are accessible. These metrics would be used to develop materials which, when inserted into everyday items during production, cause the bacteria to avoid the item. The item is inhospitable to the bacteria.
The concept takes what currently exists in the market with antibacterial coatings to the next level. Antibacterial coatings kill the bacteria which promotes bacterial evolution to survive antibacterial compounds. Cavitt’s method does not threaten the life of any bacteria which leads to antibiotic resistant bacteria (or superbugs) but instead encourages the targeted bad bacteria to move to another surface. In other words, certain formulations may allow good bacteria to flourish.
“We can start tailoring any surface to what we want to inhibit. In an operating room where you need it super clean, or in a clean room like at the Nissan plant where you’re painting, we can set it up so every surface will be unfavorable to most bacteria so the room will be much easier to clean,” said Cavitt.
“If we think about applications other than the obvious hospital applications, water treatment facilities have massive footprints. The water treatment tanks grow mold, mildew and algae. Algae is the most common biologic present in water tanks and the reason why tanks must be drained several times a year to scrub the surface,” Cavitt explained.
“If we take our material, put some of that in the paint, and then paint the interior of that water treatment tank, then all of a sudden instead of having to shut it down several times a year to scrub the tank, they only have to shut it down once or twice.”
Cavitt’s material is like putting the Lysol or Clorox back in the can, or putting soap back on the bar. “All you have to do is scrub the surface and once you scrub it down, the original surface is exposed. You just do a simple scrub and touch up paint as needed to recondition the surface and make it inhospitable to the bacteria, that’s it.”
Cavitt and his team are putting this to the test, placing the material in paint used in water treatment facilities. “We put several samples into raw sewage. After over seven million gallons of raw sewage went across the paint with our material, it inhibited microbial growth really well.”
“There are some things that become a career research project. I didn’t expect that for this,” Cavitt described as he thought back to how the research began. While volunteering with a nongovernmental organization in Indonesia following the aftershock to the record breaking 2004 earthquake and tsunami, Cavitt fell in a hospital and got a staph infection.
“In Indonesia, the word for hospital is rumah sakit, which literally means “house of pain.” Indonesians go there to die, or to be hurt. It has really bad connotations,” he said. “They have a spring at the top of the mountain and a pipe that runs from the stream down to the hospital for quick cleaning water. The pipe isn’t completely filled with water which allows air in the pipe and results in aerobic bacteria that grows. That’s probably a bad thing,” he explained.
Amid another project, Cavitt noticed bacteria would not propagate on certain compounds at a water treatment facility. He began to figure out why. “One reason was the coating of the surface was extremely smooth, like surgical grade steel, so most bacteria don’t have enough surface area to attach, but some still do attach.”
“It has to be something more than a smooth surface. Surfaces have areas that are positively charged, and others that are negatively charged. If you have a biofilm that sits on the surface, you can actually measure how much that biofilm enjoys sitting on the surface,” he explained.
“My thought is, can we figure out how that surface interacts with biofilm? If we can inhibit that biofilm growth, if we can slow it down, we make a major impact on infection rates.”
Cavitt explained that around 95 percent of microorganisms on earth reside in a biofilm. The approximately five percent that do not are those about which we worry. The five percent originate from the 95 percent. “If we can reduce the 95 percent, then how much more will that affect that five percent that’s out there? If we can stop infection at its source, or slow it down at its source, it will be much better for us,” he said.
The missing piece to the puzzle Cavitt found was not the interaction or the cell, it was not the biofilm but instead a small piece of the cell called an adhesin. “As bacteria tumble across a surface, the sticky bits are extended. If it can find something that it can stick to, it will stick. That’s primary colonization,” Cavitt described.
“Once that primary colonization occurs, other bacteria and microbes have more surface area onto which they can attach, including mold and mildew. As this occurs, you have more bacteria that aggregate and then you have the biofilm formation process, some of which happen in as little as 30 seconds.”
“We have two patents and are looking into industrial formulations,” said Cavitt. The potential uses for his material are endless spanning everyday household items, nursery items, change tables, baby toys, clothes, household appliances and more. Industrial use is also vast to include common societal infrastructure and even governmental and defense equipment applications.
Clean freaks may rejoice at this confirmation that bacteria and microorganisms grow rapidly. Cavitt’s work may someday allow enthusiastic scrubbers to put down the rubber gloves and step away from the bleach, instead reaching for a cloth and some water for a quick scrub and then getting on with their day.
See picture of biofilm formation.
See a protein structure for a mannose-specific adhesin FimH.
Learn more about the Department of Chemistry & Biochemistry, here.