Eric Bruger and I penned a review (Bruger and Marx, 2018. Current Opinion in Microbiology) that seeks to address the manner in which sequencing technologies have opened the door to whole new questions in experimental evolution. It was a joy to highlight the incredible work our field has accomplished in such a short time. I knew sequencing would be coming when I started my lab in 2005, but the magnitude of change has been incredible.
In the past months we have had two papers on the E. coli–S. enterica system that Will Harcombe developed, and worked on when he was a postdoc in the lab.
One of these (Hynes et al., 2018. Biomedical Physics and Engineering Express) reports the ability to examine communities via bioprinting, and also represented a collaboration with two of my best friends Daniel Segrè and Nate Cady.
The second of these (Harcombe et al., 2018. PNAS) just came out a few weeks ago online in PNAS. It describes Will’s amazing finding of bidirectional costly mutualism evolving between species in the lab. Repeatedly E. coli evolved to break its own metabolism to excrete galactose to S. enterica during growth together on lactose (which S. enterica can’t use) in order to obtain methionine, which S. enterica had previously evolved to produce in return. I was excited to discover that, just a couple days ago, PNAS published a commentary on our paper penned by Jennifer Farrell and Sam Brown.
Back in 2013, I co-founded KnipBio with Larry Feinberg. KnipBio’s goal is to develop Methylobacterium as an aquaculture feed ingredient that can simultaneously reduce the need for fishmeal-derived protein and provide high-value components and properties. In the past two years, our first publications have come out describing the successful use of this single-cell protein with a variety of aquaculture species (Tlusty et al., 2017. PeerJ, Hardy et al., 2018. Aquaculture Research). It has been very exciting to see work move from the lab and translate to practical outcomes.
This past Tuesday, 11/13, Siavash Riazi presented his defense for a PhD in BCB entitled “Mathematical modeling and analysis of gene expression to understand phenotypic heterogeneity and the response of Methylobacterium extorquens to formaldehyde toxicity.” His work was co-advised by Chris Remien (Mathematics) and me, and represents his first PhD student, and my first to finish here at Idaho. Many thanks to committee members, Holly Wichman, Steve Krone, and Craig Miller. And most of all congrats to Dr. Riazi!
Not nearly as exciting as the news from current and former lab members, but as of the last nearly two years I have been serving as a member of the Board of Reviewing Editors at Science. Although nobody needs more work to do, this has been a really neat opportunity to see just emerging work from many disciplines come streaming by. And it has been quite rewarding to see some of those that I expressed great excitement for make it to review and successfully out the other end, now appearing in print.
Besides new jobs, the lab now has the first alumni to be granted tenure. Alex Bradley is now an Associate Professor in Earth and Planetary Sciences at Washington University, St. Louis. Deepa Agashe is now tenured in Ecology and Evolution at the National Centre for Biological Sciences (NCBS) in Bangalore. Many congrats to you both!!!
Very excitingly, two postdocs landed PI-level jobs this year. Jannell Bazurto has landed an Assistant Professor position in Plant and Microbial Biology at the University of Minnesota, and will start her own lab in January, 2019. Jessica Lee has landed a job as a Fellow with the non-profit, GlobalViral, and also has an Adjunct Assistant Professor position at San Francisco State University. They bring the total number fo PIs to emerge from the lab to nine!
This past year has seen some big turnover in the lab with many new positions, etc. In terms of undergrads, we are excited to have Olivia Speare and Mete Yuksel on the team. They are working on protein biochemistry and phenotypic heterogeneity, respectively. Furthermore, it is exciting to have Isaiah Jordan now having started graduate school in the lab as part of the BCB graduate program. He is also working on phenotypic heterogeneity, building upon the exciting results of former postdoc Jessica Lee and others.
In getting the ball rolling on posts again, where better to start than with students. First off, I want to congratulate Alyssa Baugh on having received an overwhelming number of grad school offers, and having chosen to go to University of Georgia. She was an awesome UG in the lab, and will kick butt in grad school.
Hard to even know where to begin, but the longer I have delayed the bigger the task… In the past almost four years there have been 27 papers that have come out. Way to go team! I will thus skip mentioning all of them (see publications for all of them), but here are some highlights:
- Former grad student Nick Leiby (now Lead Data Scientist at Kyruus) published a paper describing that metabolic tradeoffs in the Lenski long-term lines primarily arose due to mutation accumulation, rather than antagonistic pleiotropy (Leiby and Marx, 2014. PLoS Biology). This differed from earlier work from Vaughn Cooper and Rich Lenski, and the difference ended up being in the fact that Biolog plates commonly report upon non-growth associated metabolism, and thus are not necessarily a good fitness proxy. Vaughn (now at Pitt) wrote a really classy Primer to our paper about this (Cooper, 2014. PLoS Biology).
- Two former grad students, David Chou (now faculty at Taiwan National University and a father of two) and Nigel Delaney (now a Vice President at GenePeeks and a new father), and collaborator Jeremy Draghi (now faculty at Brooklyn College and also a new father) put together one of my personal favorite papers that showed that epistatic interactions between mutations can be predicted from their individual effects due to the combined effects of catalysis, enzyme costs, and toxicity (Chou et al., 2014. PLoS Genetics). This built upon the classic work from the mid- to late-80s of Tony Dean, Dan Dykhuizen, and Dan Hartl that inspired me to move toward systems biology in the first place.
- We enjoyed contributing to a collaboration led by Dom Schneider at Grenoble that exposed the role of epistasis in an adaptive radiation (Plucain et al., 2014. Science).
- Former postdoc Will Harcombe (now faculty at University of Minnesota) led our contribution to an awesome collaboration with Daniel Segrè‘s lab at Boston University that used flux balance analysis and the concept that individual species in a mixed community can be approximated as behaving according to their own metabolic optimum to predict community dynamics (*Harcombe, *Riehl et al., 2014. Cell Reports; software developed is called COMETS).
- Former postdoc Josh Michener (now Wigner Fellow at Oak Ridge National Laboratory) led a paper – with excellent collaborators Stéphane Vuilleumier and Françoise Bringel from Strasbourg – showing that evolving dichloromethane use across different species of Methylobacterium always involved increasing the ability to export the chloride ions, and in the process led us to identify the beneficial mutations in M. extorquens DM4 that occurred in nature to have evolved this capacity in the first place (Michener et al., 2014. eLife).
- We enjoyed contributing to a collaboration led by Mike Springer at Harvard Medical School that showed yeast respond to the ratio of galactose and glucose (Escalante-Chong et al., 2015. PNAS).
- Former postdoc Sean Carroll (now Senior Scientist at Axcella) led a paper (Carroll et al., 2015. Microorganisms) uncovering the genetic basis of adaptation for strains evolved to grow on methanol with a foreign metabolic pathway, work that began during my own postdoc with Rich Lenski, and first published by David Chou (Chou et al., 2011. Science).
- Former postdoc Deepa Agashe (now INSPIRE Faculty Fellow at National Centre for Biological Sciences, Bangalore), her team there, N. Ceci Martinez-Gomez (now faculty at Michigan State), and our group demonstrated that adaptation to suboptimal codon usage can involve single, large-effect synonymous mutations (Agashe et al., 2016. Molecular Biology and Evolution).
- Former grad student Dipti Nayak (now LSRF Simons Foundation Fellow at University of Illinois) led a paper showing why tradeoffs in using methylamine for a carbon or a nitrogen source explains maintenance of apparent metabolic degeneracy (Nayak et al., 2016. Current Biology).
- Former grad student Sarah Douglas (now Life Science Consultant at Simon-Kucher and Partners) got both of her papers from her thesis out that, together with Will Harcombe, Lon Chubiz, and my colleague Mary Ytreberg (here at Idaho) showed the genetic basis of the in-lab evolution of between-species cooperation of a pair of species (Douglas et al., 2016. PLoS One; Douglas et al., 2017. PLoS One).
- Former postdoc Alex Bradley (now faculty at Washington University, St. Louis) and former lab manager Paige Swanson (now Director of Research Operations at Finch Therapeutics Group) led a paper showing that elimination of hopanoid production in Methylobacterium leads to overproduced carotenoids and widespread growth impairment (*Bradley, *Swanson, et al., 2017. PLoS One).
- Former postdoc Lon Chubiz (now faculty at University of Missouri, St. Louis, and yet another new father) led a paper showing that the metabolic specialist Shewanella oneidensis can evolve glucose use rapidly, but that it comes at a tradeoff for use of other substrates (Chubiz and Marx, 2017. J. Bacteriology).
- My colleague Sergey Stolyar (Research Associate Professor here at Idaho) and I have enjoyed our collaboration with Ankur Dalia and Jake McKinlay at Indiana University, which has already resulted in Ankur’s group leading a paper showing the remarkable power of natural transformation for synthetic biology in Vibrio natriegens (Dalia et al., 2017. ACS Synthetic Biology).
It would be hard for me to be more proud of how well people from my lab have done… Looking forward to future updates about the current lab, which besides Sergey Stolyar mentioned above, includes postdocs Jessica Lee, Tomislav Ticak, Jannell Bazurto, and Eric Bruger, BCB grad student Siavash Riazi, and UGs Alyssa Baugh, Caleb Renshaw, Leah Lambert, and Nick Renn.