Photo courtesy of Nancy Evelyn
The underwater world, even after so many years of exploring, still contains so many mysteries for
scientists to explore. The full breadth of the diversity of animals, plants and microorganisms living
under the ocean surface has not been fully discovered. Rapid environmental changes are
destroying the opportunity to explore this diversity further in the future. The coral reef ecosystem,
with the highest biodiversity on the planet, is extremely sensitive to those changes. Fortunately,
there are still people who are fighting for its survival. As a part of our Microbiome research
interview series, we spoke with Maite Ghazaleh Bucher, Environmental Health Sciences PhD
Candidate from the University of Georgia. Bucher is exploring the environmental influence on
microbiome of the corals.
Her passion for ocean life research started with a simple aquarium standing in her family house.
How did you first become interested in science and microbiome research?
I always had an aquarium at home growing up. I could sit in front of it and watch it for hours. Over
the years, the aquarium sparked my curiosity for living things underwater.
In high school, I took many biology classes and science electives. As a college student at UNC
Chapel Hill, I expanded my curiosity for science in environmental science and oceanography
classes. During a semester program at the UNC Institute of Marine Science, I began my adventure
studying aquatic microorganisms in Dr. Rachel Nobel’s laboratory. At the time, I was studying
Vibrio bacteria in estuaries, which are ecosystems that border with fresh- and salt-water
environments. Since some species of Vibrio cause disease, I decided to use my experience in Dr.
Nobel’s lab to study Vibrio bacteria and other microorganisms in salt-water environments,
particularly coral reefs. In 2015, I moved to Dr. Erin Lipp’s laboratory at University of Georgia to
begin my doctorate program studying the microorganisms associated with coral animals.
Can you give a summary of your project?
The focus of my doctorate program is to explore changes in coral microbiomes. Corals are
animals that excrete calcium carbonate skeletons which build the reefs and support thousands of
marine species. Corals, just like human guts, have their own microbiome which can be influenced
by variety of different factors. Just like in our guts, the coral microbiome has a huge impact on
coral functioning and health. It’s important for coral scientists to understand the interactions
between the coral and its microorganisms, especially since environmental stress, such as
increasing seawater temperatures and pollution, can cause an imbalance of the microbiome. For
example, I study how the microbiome associated with corals shifts towards a dysbiotic state when
nutrients increase in the seawater. This could potentially increase the corals’ chances of getting
sick. I also study how the microbiome changes when the coral is diseased.
Are you working on any other new projects in the field of microbiome research? If so,
can you tell us a little about these?
Yes! I am also studying the microbiome of seawater that surrounds the animals. I am working with
a team to better understand how seawater microbial communities change when atmospheric
Saharan dust concentrations increase in Looe Key Reef, FL. For example, we are investigating
how the microorganisms’ transcriptomes changes with the dust nutrient influx.
What will be a typical day for you in the lab?
The answer to this question would vary by which phase of my research I am in! Last year, I spent
most of my time collecting and processing coral samples. I used the DNeasy PowerSoil Kit to
extract the bacterial DNA from my samples for sequencing. Right now, I’m mostly on the computer
using R (statistical software) and my Mac terminal to process the sequences and create figures.
This part is actually fun because I get to piece together a microbiome story and determine whether
my hypotheses were right or wrong.
What do you find most interesting about your project? What is the most interesting or
surprising result you have found?
Coral health is delicate, and the relationship between the coral host, their microbiome, and the
environment is critical to maintaining coral health. However, understanding the complex
processes that happen within a coral is challenging. Better understanding these processes is very
important to increasing coral resilience to environmental stress and disease, and this is the part I
find most interesting! Microbes could be good guys, bad guys, neutral members of the
communities, manipulators, or opportunists depending on the host and environmental condition
– this might not be surprising in other ecosystems, but it is very interesting to coral ecologists!
With QIAGEN’s products, I’m working at the vanguard of science that seeks to understand how
microorganisms shape and contribute to life on earth.
What kind of microbiome research do you perform and how does it impact health and
disease? Where do you see this heading in the next five years?
I extract and sequence the 16S ribosomal DNA of microbial communities of coral animals. By
determining which members are present in healthy and diseased states (or under stressful
environmental conditions), we can understand disease starting points and microbiome
succession patterns. Coral disease research is shifting its focus from defining disease as a one
pathogen-one disease relationship to understanding disease as a dysbiosis. In the next five years,
it will be critical for us to define what healthy and dysbiotic microbiome states actually looks like.
What are your hobbies?
I thoroughly enjoy SCUBA diving, especially since this is how I collect my samples. I also recently
became a SCUBA instructor, so I can teach other people about the oceans and show them its
wonders. I enjoy reading about space and going to deep water fitness classes, too. In my free time, I like going to the movies, watching UNC Chapel Hill basketball games, and going out
dancing with my husband, Justin Bucher.
What are the major challenges you face in your research with regards to sample
collection, nucleic acid isolation and data analysis?
One major challenge I face in my everyday research is extracting DNA from coral mucus. In
general, extraction of bacterial DNA from coral samples can be difficult because the coral mucus
is very rich in PCR inhibitors, which decreases the quality of my DNA during amplification steps
and causes low yield.
Which MO BIO or QIAGEN products do you use/have you used in the past and what did
you like about the products?
After comparing a few kits, I found that the DNeasy PowerSoil Kit yielded the cleanest DNA with
highest concentrations. The spin columns were efficient, and the protocol only took about two
hours per 24 samples.