Events
CEMINAR
The most important community-oriented activity we sponsor is CEMINAR, formerly MicroMorning, a monthly seminar series where students and postdocs in the CEMI program present their work. Usually 2 individuals present 20-25 min talks (+ 5 min questions) to fill the hour, but on rare occasions we invite an outside speaker. CEMINAR is primarily designed to provide CEMI students and postdocs with an opportunity to practice giving a formal talk to a friendly Caltech audience. Numerous collaborations have been sparked between labs at Caltech thanks to creative connections made during these seminars. View past CEMINARS
CEMINAR
CEMINAR is on the second Wednesday of every month.
UPCOMING
Wednesday, November 12, 2025, 4:00 pm
4:00-5:00pm Chen 130
5:00-5:30pm Socializing (snacks and drinks will be provided)
"Unraveling the influence of saline environments on bacterial community structuring"
Danielle SclafaniDatta Lab
Bacteria often grow in saline environments such as tissues/gels in hosts and bodies of water. While lab studies typically focus on bacteria in idealized solutions of primarily monovalent salts, these saline environments often have an abundance of multivalent ions. Hence, we ask: How do multivalent ions change bacterial growth? We report that at sufficiently high concentrations of divalent salts, immotile E. coli do not grow as random dispersions; instead, they grow into string-like colonies comprising single cells arranged end-to-end. We conjecture that this unusual colony morphology arises due to divalent cation-mediated crosslinking of lipopolysaccharides at the surface of adjacent cells.
"Synthetic phase variation for engineered microbial consortia"
Matthieu KratzMurray Lab
Engineered microbial consortia often lose stability due to differing growth rates among strains. Traditional stabilization methods rely on cell-to-cell communication, which fails due to instability, especially in poorly mixed environments. We present a communication-free approach inspired by microbial phase variation, where genetically identical cells stochastically switch between phenotypes. The population composition remains stable and is determined by transition rates between states. Using reversible DNA inversions catalyzed by serine recombinases, we built and tested 2- and 3-state dynamic consortia. Modeling and experiments confirm that it enables robust, controllable, and communication-independent composition stabilization suitable for complex environments like bioreactors or the gut.
Social Events
In addition to CEMINAR, CEMI sponsors social events during the academic year:
Fall Poster Sessions: All CEMI labs present one or more posters on their lab’s research. This helps incoming/current students and postdocs remain up-to-date on that latest research projects going on across the campus. One attractive feature of Caltech is that students admitted in any graduate program are welcome to rotate in any lab (as long as the lab is taking students), so this poster session can open up new interests and areas for exploration. It also can spawn new collaborations between labs.
Spring Lectures and Evening Gala: To celebrate the start of the calendar year, we invite a keynote speaker from outside Caltech to give a seminar, plus a few shorter talks by assistant professors or postdocs at Caltech and other local universities. These “Spring Lectures” are open to anyone interested. As a companion event, we hold a formal gathering for a limited number of CEMI sponsors, faculty, and students and postdocs currently being supported by CEMI grants. The evening’s entertainment is organized by a different CEMI lab each year, and the evening culminates with a presentation of the “CEMI Oscars” (we are close to Hollywood, after all…), roasting CEMI members for notable achievements in the past year, all in good fun. View past lectures
Spring Happy Hour: In recognition of the fact that sometimes the most inspired ideas come when we least expect them, we promote casual conversation between all members of the CEMI community supplemented with drinks and food at the start of the spring term (no posters required!).
CEMI Spring Celebration of Science: This hour-long science program featured short lightning talks from CEMI graduate students and postdocs followed by time to talk with the speakers and socialize with our CEMI colleagues. The inaugural event was held on May 12, 2021.
Workshops
CEMI occasionally supports training courses at Caltech that provide members of the CEMI community with an opportunity for intensive training in a particular area. Any member of the CEMI community is welcome to suggest a topic for a workshop. Please contact the CEMI administrator if you have an idea. View past workshops
