Jack A. Gilbert

Principal Investigator

Professor Jack Gilbert (he/him) earned his Ph.D. from Unilever and Nottingham University, UK in 2002, and received his postdoctoral training at Queens University, Canada. From 2005-2010 he was a senior scientist at Plymouth Marine Laboratory, UK; and from 2010-2018 he was Group Leader for Microbial Ecology at Argonne National Laboratory, a Professor of Surgery, and Director of The Microbiome Center at University of Chicago. In 2019 he moved to University of California San Diego, where he is a Professor in Pediatrics and the Scripps Institution of Oceanography. Dr. Gilbert uses molecular analysis to test fundamental hypotheses in microbial ecology. He cofounded the Earth Microbiome Project and American Gut Project. He has authored more than 300 peer reviewed publications and book chapters on microbial ecology. He is the founding Editor in Chief of mSystems journal. In 2014 he was recognized on Crain’s Business Chicago’s 40 Under 40 List, and in 2015 he was listed as one of the 50 most influential scientists by Business Insider, and in the Brilliant Ten by Popular Scientist. In 2016 he won the Altemeier Prize from the Surgical Infection Society, and the WH Pierce Prize from the Society for Applied Microbiology for research excellence. In 2019 he was elected to the Philosophical Society of Washington. He also co-authored “Dirt is Good” published in 2017, a popular science guide to the microbiome and children’s health.  He serves on the board of the Genomic Standards Consortium and is the primary investigator for various research ventures, including the Earth Microbiome Project, the Home Microbiome Project, the Gulf Microbial Modeling Project, the Hospital Microbiome Project, and the Chicago River Microbiome Project.    Additionally, he founded BiomeSense Inc in 2018 to produce automated microbiome sensors.

Sarah M. Allard

Associate project scientist

Sarah (she/her) began her research career as an undergraduate, studying bees and pollination, and then moved on to an ORISE fellowship at the US Food and Drug Administration’s Center for Food Safety and Applied Nutrition, where she first became enamored with microbiology, conducting research focused on on-farm food safety and biological control of foodborne pathogens. Sarah received her PhD in Plant Science from the University of Maryland and remained at UMD for a postdoctoral fellowship in the Maryland Institute of Applied Environmental Health. There, she studied crop, soil, and water microbiomes in the context of food safety and environmental change. In her current role at UCSD, Sarah is exploring how microbiome research can be harnessed to support environmental restoration, safe and productive food systems, and the betterment of human health. Sarah is committed to helping students pursuing microbiome research prepare a diverse skillset to enable effective interdisciplinary research and communication. She coordinates an interdisciplinary Research Experience and Mentoring program designed to build a robust mentoring environment and facilitate hands-on training for local undergraduate students interested in pursuing STEM careers. She is also the diversity coordinator for the Microbiome and Metagenomics Center at UCSD, part of NIH’s Nutrition for Precision Health program, and she is an editor at mSystems. More information can be found on her website, and her publications can be seen here.


Gertrude Ecklu-Mensah

Assistant Project Scientist

Gertrude earned her Ph.D. in Biochemistry (2017) in a sandwich program funded by the Danish Ministry of Foreign Affairs (DANIDA), from the University of Copenhagen and the University of Ghana. Her research focused on severe malaria pathogenesis in children, specifically investigating ICAM-1 binding PfEMP1 in pediatric cerebral malaria. Gertrude was awarded a one year Global Health NIH/Fogarty Postdoctoral Fellowship under the VECD consortium in 2018 to study malaria transmission biology at the University of Health and Allied Sciences, Ghana. Beginning August 2019, she joined the Gilbert lab as a postdoctoral fellow, to understand the biological mechanisms used by the gut microbiota to influence the human host metabolism particularly during malnutrition. Additionally, she is interested in exploring broadly the interactions between diet and the microbiota-gut-brain axis, and potential interconnections of the gut microbiota in malaria and non-communicable diseases.

Postdoctoral Scholars


Megan S. Hill

Postdoctoral Scholar

Megan (she/her, previously known as Megan Thoemmes) received her PhD in 2019 from the Applied Ecology department at North Carolina State University, under the direction of Dr Rob Dunn. Her work focuses on the microbes and arthropods found on and around mammal bodies, including those associated with humans, chimpanzees, and Key Largo woodrats. She is interested in how the built environment shapes species interactions and what factors drive differences among mammal structures, as well as how those differences affect individual health and well-being.

In the Gilbert lab, Megan primarily studies microbial selection on the International Space Station and the use of novel intervention methods to reduce antibiotic resistance and virulence in pathogens at Rady Children’s Hospital.  Previous work includes the development of the Meet Your Mites project and work on the Wild Life of Our Homes project. Her publications can be found here.

Graduate Students

Marisol (Dottie) Dothard

PhD Student

Dottie Dothard (she/her) is a second-year PhD student in the Gilbert lab at the University of California, San Diego. Dottie completed degrees in Biology and Classical Voice from Bard College in 2017. She went on to complete a post-baccalaureate research program at the University of Pennsylvania, where she used a mix of bioinformatics and molecular biology approaches to hunt for novel viruses in the human lung. After finishing her post-baccalaureate studies in 2019, she earned a Master’s Degree in Molecular Biology, Cellular Biology, and Biochemistry from Boston University. Her thesis work focused on unique motility mechanisms of several marine microbe strains. During her Masters, Dottie was awarded the prestigious National Science Foundation Graduate Research Fellowship Program (NSF GRFP). Dottie is still fascinated by the sociological doings of microbes and aims to focus her PhD research at UCSD on increasing our understanding of the microbiomes of transgender individuals in order to better inform transgender healthcare. In her free time, Dottie is the editor of a small literary magazine through the Biomedical Sciences program at UCSD and enjoys freelance writing gigs, reading, and editing. Dottie is a passionate community advocate and is involved in several community service projects including volunteer programs oriented to increase book access for incarcerated individuals and paid community advocacy as Community Liaison for the Black Graduate Education Living and Learning Community at UCSD.


Neil Gottel

PhD Student

Neil (he/him) graduated from the University of Illinois at Urbana-Champaign with a B.S. in Integrative Biology, where he studied the nitrogen fixing microbes living within the potential biofuel crop Miscanthus giganteus. He then studied the microbiome of various poplar tree species at Oak Ridge National Laboratory, then attended graduate school at the University of Texas Austin. He returned to Chicago to work at Argonne National Laboratory, and joined the Gilbert lab as a technician. After surviving the Technician Battle Royale, he became the lab manager at its University of Chicago location. He is now at UCSD, in Scripp’s marine biology graduate program. His publications can be found here.



Sho Kodera

PhD Student

Sho (he/him) graduated from UC San Diego with a B.S. in Ecology, Behavior, and Evolution. He then obtained his M.S. under Dr. Stuart Sandin at Scripps Institution of Oceanography, focusing on coral reef ecology and life history. He also worked as a staff research associate with the 100 Island Challenge project at Scripps, where he conducted extensive field surveys and data collection in various tropical coral reef communities. Sho has spent over 350 hours underwater conducting scientific SCUBA dives in remote islands across the Pacific and the Caribbean. He now conducts research in marine microbial ecology; his research interests involve understanding broad-scale ecological concepts through the examination of microbial dynamics in rivers, marine mammals, humans, and coral reefs. 


Emily Kunselman

PhD Student

Emily (she/her) graduated from the University of California, San Diego with a B.S. in Marine Biology. As an undergraduate, she completed her honor’s thesis on the microbiome of the Olympia oyster in the Puget Sound. She continues to work on oysters during her PhD, studying how an oyster virus, OsHV-1, impacts the oyster microbiome and how temperature dictates viral proliferation. She has also expanded into a new mollusk, the endangered white abalone.  She studies how the microbiome of white abalone responds to a bacterial disease called Withering Syndrome. Emily is broadly interested in aquaculture, which has driven her to study the interactions between climate change, disease and the microbiome, all of which greatly impact shellfish and aquaculture operations.

Kara Wiggin Photo

Kara Wiggin

PhD Student

Kara (she/her) graduated from Northeastern University in 2014 with a B.S. in Environmental Science. In 2019, she obtained her M.S. at Cal State Long Beach in Dr. Erika Holland’s Tox Lab, where she studied the detection and toxicity of microplastic pollution. She is now pursuing her PhD in Marine Biology at SIO. Kara is still pursuing questions related to microplastic pollution, but is now approaching her research from a microbiology perspective, studying the role of microplastics in pathogen transmission in the marine environment.

Ryan Chung

Masters Student

Ryan graduated from UCSD with his B.S. in Marine Biology and minor in Environmental Systems in 2023. He is currently pursuing a masters degree in Marine Biology at SIO. Ryan is broadly interested in the interplay between marine organisms and human health, with a recent focus on marine microbes and their pathogenicity in humans. As an undergraduate lab technician, he helped conduct experiments aimed at quantifying microplastic pollution and microplastics as pathogen vectors in oysters. Ryan hopes to continue in academia before transitioning to a teaching role, where he hopes to inspire students to pursue research opportunities as undergraduates.

Vanessa Minnis

Masters Student

Vanessa (she/her) graduated from UCSD with her B.S. in Environmental Systems/Environmental Chemistry in 2023. Vanessa is interested in ecotoxicology and the impacts on human health through the lens of microbial environments. She has conducted independent research, under the supervision of Dr. Megan Hill, on the microbiome of built environments, specifically focusing on antibiotic resistance from isolates collected on the International Space Station. Vanessa is pursuing her M.S. in Marine Biology where she continues researching the impacts the environment has on human health and microbial communities.

Joshua Tran

Masters Student

Joshua (he/him) graduated from UC San Diego with a B.S. in Human Biology in 2023. As an undergraduate, Joshua’s research interest broadly involved studying the interactions between the gut microbiome and cancer development under Dr. Jack Gilbert (Scripps Institute of Oceanography/UCSD Department of Pediatrics) and Dr. Georgia Sadler (UCSD Moores Cancer Center). Now, as an M.S. biology student in the Gilbert lab, Joshua is thrilled to learn more about the microbial interactions in and around the body and their role in health but specifically, cancer. His current research aims to understand how dietary interventions impact inflammation and microbiome structure post-colonoscopy for elevated colorectal cancer risk patients.

Undergraduate Students

Chris Zhang

Undergraduate Student

Chris is a 3rd year undergraduate Marine Biology major at UCSD. He enjoys studying anything and everything that relates to marine life and the oceans, and he is excited to research how microbiology relates to ocean life. Chris hopes to go to graduate school for an MS for Marine Biology. He joins the Gilbert lab as part of the National Cancer Institute-funded Creating Scientists to Address Cancer Disparities program. 



Mariana Salas Garcia

Lab Manager

Mariana is an experienced lab manager with a strong background in biochemistry, pre-medicine, and microbiology. With a B.A. in Biochemistry and Pre-Medicine from Judson University, her passion for understanding the microbial world and its impact on human health has driven her specialization in microbiome research. Mariana has a Master’s degree in project management, allowing her to effectively oversee and coordinate diverse, multidisciplinary projects within the laboratory. With her entrepreneurial mindset and problem-solving abilities, she excels in resource management, workflow optimization, and ensuring the successful execution of research initiatives. Mariana’s dedication and leadership skills foster an efficient and productive lab environment, promoting collaboration and innovation among the team members. Her publications can be found here.


Mary Buschmann

Grant Writer and Coordinator

Mary holds a BA in Biology from Concordia University, Ann Arbor, MI, and a PhD in Cell and Cancer Biology from the University of Cincinnati. She did her postdoctoral research at the University of Chicago as a Ruth L. Kirschstein National Research Service Award Fellow, studying gut epithelial barrier function. Prior to joining the Gilbert group, Mary spent almost 5 years overseeing the Chicago Pancreatic Cancer Initiative at the University of Chicago, which was a clinical research program studying ways to use patient genomic, clinical, and demographic data and personalized cell line models to improve understanding and treatment of the disease. Concurrent with this, she managed the University of Chicago’s Department of Surgery grant and clinical research portfolio. In the Gilbert lab, Mary utilizes these experiences to coordinate collaborative research programs, prepare funding applications and research articles, and manage human research regulatory affairs for the group.


Megan Preovolos


Megan is a native San Diegan (born and raised!) and joined the Gilbert Lab January 2, 2019, before anyone else had actually arrived in San Diego.  She is a UCSD Alumni, graduating with her BS in Cognitive Science in 2007.  In the Gilbert Lab,  Megan provides administrative support in many aspects of the lab, trying to do everything she can to make the lab members’ lives just a little bit easier. Outside of work Megan loves to travel, scuba dive, and train and fundraise with Team Challenge in honor of the Crohn’s and Colitis Foundation.  

Nicole Bardales

Laboratory Technician

Nicole (she/her) is an Orange Coast College Alumni with two Associates degrees in Chemistry and Biology. Nicole transferred to UCSD to obtain her Bachelors in Biochemistry and graduated in 2023. She was intensely involved in the American Medical Student Association and gained over 300 hours in clinical experience from Scripps Green Hospital and St. Joseph Hospital. Nicole is a pre-medical student interested in research to help create novel theories in science. She splits her time between the Gilbert lab and Dr. Georgia Sadler’s group (UCSD Moores Cancer Center) and is part of the National Cancer Institute-funded Creating Scientists to Address Cancer Disparities program. 

Previous Lab Members

  • Rachel Diner (postdoc) – Assistant Professor of Biological Sciences, University of Memphis
  • Carolina Carpenter (graduate student) – Graduate Student, SIO (Andy Allen lab)
  • Zachary Daniel (undergraduate research assistant) – Graduate Student, SIO (Jensen lab)
  • Davis Bone (high school and undergraduate research assistant) – Undergraduate Student, Johnson & Wales University
  • Antoinette Jane (AJ) Dizon (undergraduate research assistant, REM program)- Undergraduate Student, California State University San Marcos
  • Daysi Manrique (undergraduate research assistant, SURF program)- Undergraduate Student, Pomona College
  • Nolan Sigmund (laboratory assistant)- Laboratory Technician, UCSD Psychology
  • Ella Rushton (visiting undergraduate researcher) – Undergraduate Student, University of the West of England, UK
  • Maria Gjerstad Maseng (visiting graduate student) – Graduate Student, University of Oslo and Bio-Me
  • Alexander Mahnert (visiting postdoc) – Postdoc, Medical University of Graz, Austria
  • Holly Lutz (postdoc and assistant project scientist) – Postdoctoral Affiliate, Andersen Lab, Scripps Research Institute
  • Lisa Marotz (postdoc) – Microbiome Scientist, Native Microbials, Inc
  • Farhana Ali, MD (clinical research fellow) – Pediatric Gastroenterologist, Intermountain Primary Children’s Hospital
  • Jessica Gallant-Swafford, MD (clinical research fellow) – National Jewish Health
  • Leslie Chiang, MD (clinical research fellow)
  • Kathryn Van Artsdalen (laboratory technician)
  • Natalie Grayson (graduate student) – PhD Student, Moore lab at SIO-UCSD
  • Promi Das (postdoc) – Project Manager, Center for Microbiome Innovation
  • Sophia Carryl (graduate student) – Postdoctoral Research, Harvard (Haber lab)
  • Anukriti Sharma (postdoc) – Research Scientist II, Department of Quantitative Health Sciences, Lerner Research Institute, Cleveland Clinic
  • Ali Sjaarda – University of Chicago
  • Alyson Yee – MD Student, University of Chicago Medical School
  • Beatriz Pelnaver – Assistant Professor, University of Illinois Chicago
  • Ben Temperton – Senior Lecturer in Bioinformatics, University of Exeter, UK
  • Bonnie Laverock – Research Fellow at Auckland University of Technology
  • Cesar Cardona – Sr. Bioinformatics Cloud Engineer, Second Genome, CA
  • Chris Marshall – Assistant Professor of Applied and Environmental Microbiology, Marquette University, WI
  • Daniel Smith – Bioinformatics Programmer, Baylor College of Medicine
  • Elle Hill – Research Assistant/Technician, University of Chicago & Argonne National Library
  • Haitao Wang – Postdoctoral Research University of Greifswald, Germany
  • Iratxe Zarraonaindia –  Ikerbasque Research Associate, Department of Genetics, Physical Anthropology and Animal Physiology, Univ of the Basque Country UPV/EHU, Spain
  • Jarrad Marcell-Hampton – Postdoctoral Researcher (Bridge to Faculty Program), University of Illinois Chicago
  • Kassandra Brown – Princeton/Yale
  • Kim M. Handley – University of Aukland
  • Lauren Cralle – MD Student, University of Massachusetts Medical School
  • Leron Perez – Graduate Student, Stanford School of Medicine
  • Madeline Kim – Medical Student at the Icahn School of Medicine
  • Melissa Dsouza – Commense Health, Boston MA
  • Miles Richardson – PhD Student, Columbia University
  • Na Fei – Postdoctoral Research Chang Lab, University of Chicago
  • Naseer Sangwan – Director of Microbiome Core, Cleveland Clinic
  • Nicole Scott – Biota Inc
  • Pamela Weisenhorn – Argonne National Laboratory
  • Sean M. Gibbons – Assistant Professor, Institute for Systems Biology, University of Washington
  • Simon Lax – Postdoctoral Research Associate, MIT
  • Simon Thomas – Principle Researcher, Plymouth Marine Laboratory, UK
  • Tom Kuntz – Postdoctoral Research, Harvard (Huttenhower lab/Microbiome Analysis Core)
  • Victor S. Pylro – Argonne National Laboratory
  • Wyatt Arnold – PhD Student, Yale University