Teens swipe a door handle and find an antibiotic | Science News for Students

Teens swipe a door handle and find an antibiotic

New types of bacteria are everywhere — and some might make medicines we can use
Jun 21, 2019 — 6:45 am EST
a photo of the trio of teen scientists who found a new bacterium

Atlantis Aziz-Dickerson (left), Joyceline Dweh (center) and D’Asia Buchanan (right) swabbed a door handle, a smartphone and a hand dryer — and found a new bacterium.

A. Sue Weisler

Three high school seniors swabbed a door handle, a smartphone and a hand dryer. They never expected to find anything truly new. But discoveries can turn up anywhere. And these young women helped to find a brand-new bacterium. One day, the microbe might even help produce new antibiotics.

Atlantis Aziz-Dickerson, 18, Joyceline Dweh, 17, and D’Asia Buchanan, 17, are all seniors at Rochester Prep High School in New York. The teens were chosen during the fall of their senior year to participate in a Capstone program. It pairs teens at Rochester Prep with professors at the nearby Rochester Institute of Technology (RIT). Some other Capstone students chose to study photography, computer science or game design. Atlantis, Joyceline and D’Asia chose microbiology, the study of things too small to see with the naked eye.

“I’ve always been interested in science, but I wasn’t sure what type of science I wanted to do,” D’Asia says. “Bacteria sounded like a good thing. And I thought I would get the best experience, because it was hands-on.”

The three teens teamed up with RIT scientist André Hudson. As a biochemist, he studies the chemistry of living things. He and his laboratory members are in to  bioprospecting. Prospectors are people who search Earth for valuable substances. They might pan for gold, for example, or search for oil. Bioprospectors search for new organisms that could prove valuable, such as sources of new drugs.

To look for new bacteria, Hudson doesn’t have to go far. People have found only a tiny fraction of the microbial species on Earth. New species are hiding in the soil and on surfaces all around us.

And some of them might aid medicine. Bacteria produce chemicals that can kill other bacteria as they battle each other in tiny turf wars. Scientists have turned those chemicals into antibiotic medicines to fight our own infections. So far, those medicines have served people well. But now there is a need for new weapons. That’s why Hudson’s lab goes bioprospecting. “We have to look at all the possibilities,” he says. After all, many of the antibiotics that doctors use today originally came from soil bacteria.

When Atlantis, Joyceline and D’Asia started in Hudson’s lab, they thought they would be sampling soil. Instead, Hudson asked them to sample things that people touch every day. So D’Asia swabbed her smartphone. Joyceline sampled the hand dryer in the bathroom. Atlantis swabbed the door handle to the largest science classroom on the RIT campus.

Going on a bug hunt

Working with Hudson and others, the three teens grew the bacteria from their swabs in dishes in the lab. One species from the door handle stood out. It formed bright yellow colonies. The girls then sequenced its DNA: They studied the order of its nucleotides — chemical building blocks that made up DNA’s code. That code revealed that this germ belongs to the genus Yimella and probably was a new type, or strain. The bacterium now has a name: Yimella sp. strain RIT 621 (RIT for the school where it was found).

“I was surprised,” Joyceline says. “When I first started doing the project, I didn’t think anything would come out of it.” But she and the others had found a new germ living on an ordinary door handle at RIT. Together with Hudson and other members of his lab, these teens published their findings April 25 in Microbiology Resource Announcements.

a photo of the bacteria as grown in a colony (left) and magnified showing grape-like clusters (right)
The bacteria that Atlantis, Joyceline and D’Asia grew formed golden colonies (left). When highly magnified (right), the bacteria — a strain of the genus Yimella — look like round grapes.
A. Hudson

This new Yimella also turned out to have a useful talent. Atlantis, Joyceline and D’Asia extracted chemicals the bacterium made. They found the bacterium produced something that could kill two other types of bacteria. Their Yimella could kill a strain of Escherichia coli (or E. coli). The other was a strain of Bacillus subtilis.

“I was scared at first because I thought it could be another superbug” — some microbe that resists antibiotics, Atlantis says. “Then when I learned it killed E. coli, I was excited because it’s doing some good.”

Yimella’s germ-killing trait might lead to a new antibiotic. But that would be true only if Yimella’s antimicrobial chemical was one that scientists hadn’t seen before.

“It’s a start,” says Brittany Bennett. She is a microbiologist at the University of Hawaii at Manoa. “There’s still a lot of work that needs to be done” to identify the antimicrobial compounds and see whether they’re new. “It’s a long process,” she notes. But the new finding does show promise, she says. “These students have shown you can go just about anywhere and find something new.”

It’s essential to keep looking, adds Blanca Barquera. She’s a microbiologist at Rensselaer Polytechnic Institute in Troy, N.Y. “It’s pretty impressive what these students did,” she says. In fighting germs, she explains, “Anything we can do now is helpful. The bacteria are winning, and we are not doing very much [about it].”

Atlantis and Joyceline both want to continue studying science in college. D’Asia has decided to pursue her interest in math. And Hudson has already signed up to have more high school students join his lab to help out in his bioprospecting. “I love it,” he says. “When I was a wide-eyed kid and intimidated, I [worked] in someone’s lab… That’s what made me a scientist today. I’m paying it forward.”

Power Words

(more about Power Words)

antibacterial     Having properties that tend to destroy or limit the growth or reproduction of bacteria.

antibiotic     A germ-killing substance, usually prescribed as a medicine (or sometimes as a feed additive to promote the growth of livestock). It does not work against viruses.

antimicrobial     A substance used to kill or inhibit the growth of microbes. This includes naturally derived chemicals, such as many antibiotic medicines. It also includes synthetic chemical products, such as triclosan and triclocarban. Manufacturers have added some antimicrobials to a range of sponges, soaps and other household products to deter the growth of germs.

bacteria     (singular: bacterium) Single-celled organisms. These dwell nearly everywhere on Earth, from the bottom of the sea to inside other living organisms (such as plants and animals). Bacteria are one of the three domains of life on Earth.

bug     The slang term for an insect. Sometimes it’s even used to refer to a germ. 

chemical     A substance formed from two or more atoms that unite (bond) in a fixed proportion and structure. For example, water is a chemical made when two hydrogen atoms bond to one oxygen atom. Its chemical formula is H2O. Chemical also can be an adjective to describe properties of materials that are the result of various reactions between different compounds.

chemistry     The field of science that deals with the composition, structure and properties of substances and how they interact. Scientists use this knowledge to study unfamiliar substances, to reproduce large quantities of useful substances or to design and create new and useful substances.

defense     (in biology) A natural protective action taken or chemical response that occurs when a species confront predators or agents that might harm it. (adj. defensive)

DNA     (short for deoxyribonucleic acid) A long, double-stranded and spiral-shaped molecule inside most living cells that carries genetic instructions. It is built on a backbone of phosphorus, oxygen, and carbon atoms. In all living things, from plants and animals to microbes, these instructions tell cells which molecules to make.

E. coli     (short for Escherichia coli) A common bacterium that researchers often harness to study genetics. Some naturally occurring strains of this microbe cause disease, but many others do not.

genus     (plural: genera) A group of closely related species. For example, the genus Canis — which is Latin for “dog” — includes all domestic breeds of dog and their closest wild relatives, including wolves, coyotes, jackals and dingoes.

germ     Any one-celled microorganism, such as a bacterium or fungal species, or a virus particle. Some germs cause disease. Others can promote the health of more complex organisms, including birds and mammals. The health effects of most germs, however, remain unknown.

high school     A designation for grades nine through 12 in the U.S. system of compulsory public education. High-school graduates may apply to colleges for further, advanced education.

microbiology     The study of microorganisms, principally bacteria, fungi and viruses. Scientists who study microbes and the infections they can cause or ways that they can interact with their environment are known as microbiologists.

nucleotides     The four chemicals that, like rungs on a ladder, link up the two strands that make up DNA. They are: A (adenine), T (thymine), C (cytosine) and G (guanine). A links with T, and C links with G, to form DNA. In RNA, uracil takes the place of thymine.

smartphone     A cell (or mobile) phone that can perform a host of functions, including search for information on the internet.

species     A group of similar organisms capable of producing offspring that can survive and reproduce.

strain     (in biology) Organisms that belong to the same species that share some small but definable characteristics. For example, biologists breed certain strains of mice that may have a particular susceptibility to disease. Certain bacteria or viruses may develop one or more mutations that turn them into a strain that is immune to the ordinarily lethal effect of one or more drugs.

superbug     A popular term for a disease-causing germ that can withstand medicines.

Citation

Journal: A. Parthasarathy et al. Isolation, whole-genome sequencing, and annotation of Yimella sp. RIT 621, a strain that produces antibiotic compounds against Escherichia coli ATCC 25922 and Bacillus subtilis BGSC 168. Microbiology Resource Announcements. Vol 8, April 25, 2019, e00329-19. doi: 10.1128/MRA.00329-19.