Isolation and Characterization of Naturally Occurring Bacteria from Equine Uterus By Samantha Howe
My current project is focused on characterizing the microbiome of the equine uterus. During my time as an Animal Science Research Scholar in Dr. Udaya DeSilva’s laboratory, I helped with a project aimed at identifying bacterial species that inhabit healthy equine (horse) uteri. There are numerous steps involved in this project. I start by receiving uterine fluid samples from healthy mares. Next, I plate the samples onto both Blood and MacConkey agar plates. Once I have bacterial growth, I perform single colony purification and send each culture to the Oklahoma Animal Disease Diagnostics Lab (OADDL) to be identified. If the lab is unable to identify the samples, I culture them in Terrific Broth. Once growth occurs, I perform DNA extraction. Next, I perform PCR regions on V1-V9 of the 16s ribosomal RNA. Upon completion, I send the samples for sequencing. The study identified 160 different genera of bacteria that live in the uteri of healthy mares. Some of
these organisms have never been reported before and none have ever been reported in the uteri of mares. I am interested in two of these organisms that sometimes represent 50% or more of the bacteria found in some mares. One is an organism that belongs to the genus Pseudomonas and the other is an organism that belongs to the genus Terisoporobacter. I am interested in the Pseudomonas organism because of another bacterium belonging to the same genus, Pseudomonas aeruginosa. Pseudomonas aeruginosa is a known pathogen in human and animal reproductive tracts, however the Pseudomonas sp. I am studying seems to thrive in healthy animals. In addition, I am also interested in Terisoporobacter, because it has never before been reported in an animal. The goal of my current research project is to biochemically and microbiologically characterize microbial populations in healthy equine uteri in order to determine their
function and purpose. In doing so, I hope these organisms could someday be used as probiotics in mammalian reproductive tracts to treat issues like infertility and endometriosis. The mammalian uterus has always been considered a sterile, pristine environment to be able to sustain a fetus. Any indication of the presence of an extraneous organism called for intervention with broad-spectrum antibiotics and antifungal agents. This paradigm has recently been challenged by the observation of commensal bacteria in healthy human placenta. Subsequently, many laboratories (including the laboratory I work in) have proven that a dynamic bacterial population exists in the uteri of several mammalian species. However, the current veterinary/medical approaches call for comprehensive antibiotic treatment of uteri at the first indication of infection. The function, if any, of most of these bacteria are not known at this time. My research is important because if I am successful, these organisms could someday be used as probiotics in mammalian reproductive tracts.
PHOTOS / REBEKAH ALFORD
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