From Soil to Spotlight: The Streptomycete That Shined by Alexis L.P.

As a student enrolled in BIO 145, I have had the privilege to participate in the Tiny Earth Project. Tiny Earth is an organization that aims to give students the opportunity to gain hands-on research experience and address issues such as the rise of antibiotic resistance and the protection of soils from erosion and climate change. I did not have a lot of opportunities to gain research experience prior to this class. So when I heard about the Tiny Earth project and the responsibilities associated with BIO 145, I was excited to start my journey as a Tiny Earth scientist.

 A Yellow Discovery with a Bright Potential

A Safe ESKAPE Assay testing Soil isolates against Enterococcus raffinosus

I first began my project by collecting soil samples to make serial dilutions and picking isolates for safe ESKAPE testing. I was quite interested to see what my soil samples could yield since my sample was collected on a rainy day and I saw a variety of organisms such as worms and ground beetles. While analyzing my serial dilution plates and picking out potential isolates for testing, I came across a Streptomyces colony that stood out due to its striking yellow pigment. But it didn't just sit there, it aggressively stained the neighboring bacteria and the agar a bright yellow hue. I was fascinated by this rich yellow pigment that I chose to isolate this microbe and  to continue further testing. Upon safe ESKAPE testing, I discovered that this yellow isolate was effective against Gram-positive bacteria such as S. epidermidis and B. subtilis. However, under UV light, this yellow microbe fluoresced a brilliant yellow and illuminated like a bright star. I was so in awe of the characteristic that I knew that I needed to do more testing on this special microbe. At first, it only seemed like the metabolites produced by this microbe were only effective against Gram-negative bacteria. However, that all changed when I chemically extracted the compound, and it showed effective antimicrobial activity against both Gram-positive and Gram-negative! By the end of characterizing my isolate, I learned that exploring new things just because you find it interesting is worth it. The curiosity that I had for this microbe is what kept me engaged and persistent with my research. I would have never known that this microbe would glow under UV black and produce a compound that has that capability of killing both Gram-positive and Gram-negative bacteria if I wasn’t curious. Tiny Earth has taught me a valuable lesson that discovery does not always happen on the first try, sometimes it starts off as a simple glow on a plate and a reason to keep going.

The Importance of Antibiotic Discovery and the Challenges It Faces

This project’s main goal is to emphasize the need to discover new antibiotics. Antibiotics are an important tool to treat bacterial infections, however, its effectiveness and constant use has led to the rapid rise of antibiotic-resistant bacteria. Despite these evolving bacteria and the ineffectiveness of antibiotics we have today, the development of new antibiotics has slowed down tremendously and has created a gap of innovation during a time where antibiotic resistance is at its highest and responsible for taking the lives of many victims. It is up to scientists like us to advocate for research and awareness against antibiotic resistance.

References:

Hernandez, S., Tsang, T., Bascom-Slack, C., Broderick, N., & Handelsman, J. (2020). Tiny earth: A research guide to student sourcing antibiotic discovery. XanEdu.