- Princiotta, S.D., A. VanKuren, C.E. Williamson, R.W. Sanders, M.S. Valiñas. 2023. Disentangling the role of light and nutrient limitation on bacterivory by mixotrophic nanoflagellates. Journal of Phycology 00:1-6, online June 2023. [doi:0.1111/jpy.13358]
- Millette, N.C., R.J. Gast, J.Y. Luo, H.V. Moeller, K. Stamieszkin, K.H. Andersen, E.F. Brownlee, N. Cohen, S. Duhamel, S. Dutkiewicz, P.M. Glibert, M.D. Johnson, S.G. Leles, A.E. Maloney, G. McManus, N. Poulton, S.D. Princiotta, R.W. Sanders and S. Wilken. 2023. Mixoplankton and mixotrophy: Future research priorities. Journal of Plankton Research. fbad020. [doi:10.1093/plankt/fbad020]
- Princiotta, S.D., Nguyen, T.** and R.W. Sanders. 2023. High abundances and negligible grazing during winter by the mixotrophic chrysophyte Dinobryon. Fottea 23:201-207. [doi: 10.5507/fot.2022.020]
- Grattepanche, J.-D., W.J. Jeffrey, R.J. Gast, R.W. Sanders. 2022. Diversity of microbial eukaryotes along the West Antarctic peninsula in austral spring. Frontiers in Microbiology 13:844856 [doi:10.3389/fmicb.2022.844856]
- Sanders, R.W. 2021. Protists: Flagellates and Amoeba. in: Earth Systems and Environmental Sciences, Reference Module. Elsevier. doi: 10.1016/B978-0-12-819166-8.00079-7
Our colleague Wade Jeffrey, a professor at Western Florida University and collaborator on our NSF Antarctic grant, has a show of wonderful photos that he has taken during his numerous trips (including several with us) in the Southern Ocean. Here’s a link.
Bob Sanders (TU), J.D. Grattepanche (TU), Nicole Millett (WHOI, now at VIMS), Wade Jeffrey (UWF) and Leila Harris (UWF) returned in December 2019 from another oceanographic expedition off the west coast of the Antarctic peninsula. This cruise on the Nathaniel B. Palmer was the second of two cruises to investigate the ecology and diversity of phagotrophic phytoplankton (mixotrophs). We consider it a success, though delays in the return of samples to the US and shutdown of out labs by the pandemic put us far behind schedule in our analyses. We were scheduled for another in April 2021, but the pandemic intervened there too, putting a halt to all US Antarctic expeditions. for the 2021 season.
Bob Sanders was joined by Jay Diii Grattepanche and Chris Carnivale from Temple, Wade Jeffrey and Leila Harris from Western Florida University, and Nicole Millette from WHOI on an early Austral spring research cruise to the Western Antarctic Peninsula. Supported by NSF. Here’s a link to a few photos: Antarctica Oct to Dec 2019. Our cruise designation was “Mixotrophic Eukaryotes in Antarctica: Their Habitat, Environmental Adaptation & Diversity (MEATHEAD)”
J.D. Grattepanche (TU), Becky Gast (WHOI), Wade Jeffrey (UWF) and Ari Simmering (UWF) have recently returned from an oceanographic voyage off the west coast of the Antarctic peninsula. This cruise on the Laurence M. Gould was the first of two cruises to investigate the ecology and diversity of phagotrophic phytoplankton (mixotrophs). Check out the cruise through Becky’s blog – it’s on the right-hand column of her website: https://www2.whoi.edu/staff/rgast/
Bob Sanders and Laura Toran (Temple University Earth & Environmental Sciences) co-sponsored Gene Likens’ recent award of the Franklin Medal in Earth & Environmental Science. Here’s a link to the Franklin Institute’s page of the honorees and award ceremony for 2019.
(Bob Sanders, Gene Likens, Laura Toran)
Gast, R.J., S.A. Fay and R.W. Sanders. 2018. Mixotrophic activity and diversity of Antarctic marine protists in austral summer. Frontiers in Marine Science 5:13 is available with all of the papers in that special edition as an e-book available at the link here.
Bob Sanders participated in writing a paper on the biogeography of protists that have an innate ability to photosynthesize, but also are phagotrophic.
Leles, S.G., A. Mitra, K.J. Flynn, U. Tillmann, D. Stoecker, H.J. Jeong, J. Burkholder, P.J. Hansen, D.A. Caron, P.M. Glibert, G. Hallegraeff, J. Raven, R.W. Sanders, M. Zubkov. 2019. Sampling bias misrepresents the biogeographic significance of constitutive mixotrophs across global oceans. Global Ecology and Biogeography 28:418-428. [doi: 10.1111/geb.12853]
Jean-David Grattepanche, a broadly-experienced protistologist, has joined the lab to work on our recently funded NSF grant that includes new research curises to Antarctica. J.D. has combined the power of bioinformatics, ecology and evolution to study eukaryotic microbes, with a focus on the “SAR” clade (Stramenopila, Alveolata and Rhizaria; (Grattepanche, et al. 2018) in marine and freshwater settings. He moves to Philadelphia from the Smith College lab of Laura Katz.
Congratulations to Andrew Van Kuren for winning a 2018 College of Science and Technology Outstanding TA award.
A new paper, by Zaid McKie-Krisberg, Bob. Sanders and Becky Gast, has been accepted in Frontiers of Marine Science. Evaluation of mixotrophy-associated gene expression in two species of polar marine algae. [doi: 10.3389/fmars.2018.00273] .
Gast, R.J., S.A. Fay and R.W. Sanders. 2018. Mixotrophic activity and diversity of Antarctic marine protists in in austral summer. Frontiers in Marine Science 5: 1-12. https://doi.org/10.3389/fmars.2018.00013
Bob Sanders participated in writing a paper on the biogeography of protists that acquire the ability to photosynthesize via symbiosis or kleptoplasty.
Leles, S.G., A. Mitra, K.J. Flynn, D.K. Stoecker, P.J. Hansen, A. Calbet, G B. McManus, R.W. Sanders, D.A. Caron, F. Not, G. M. Hallegraeff, P. Pitta, J.A. Raven, M.D. Johnson, P.M. Glibert, S. Våge. 2017. Oceanic protists with different forms of acquired phototrophy display diverse biogeographies and abundance. 2017. Proceedings of the Royal Society B 284: 20170664. [doi: 10.1098/rspb.2017.0664]
A paper based on a presentation given by Steffi Moorthi at a “Symposium on Aquatic Microbial Ecology (SAME)” was recently published. Moorthi, S.D., R. Ptacnik, R.W. Sanders, M. Busch, R. Fischer, H. Hillebrand. 2017. The functional role of planktonic mixotrophs in altering seston stoichiometry. Aquatic Microbial Ecology 79: 235-245. [doi:10.3354/ame01832]
Sarah Hamsher, previously at the University of Colorado, Boulder has joined the lab. Her research interests revolve around the evolutionary relationships of eukaryotic microorganisms – especially diatoms.
Research Faculty Position Has Been Filled
The Ecological Impact of Mixotrophic Algae in a Changing Arctic Climate
A 2-year non-tenure track research position is available starting as early as February 1, 2017 as part of a project investigating Arctic protists that have the ability to use both photosynthetic and heterotrophic nutrition (mixotrophs). The goals of the project are to: 1) study the physiology of different algal groups that have been identified as mixotrophic and occur in the Arctic seas; this includes an examination of how changes in irradiance, temperature and dissolved nutrients affect photosynthesis versus bacterivory; 2) evaluate differential gene expression using RNAseq methods in cultures where grazing is high versus low for a subset of species from each of the major groups; and 3) relate grazing rates to the abundance of the Arctic species determined using qPCR and environmental DNA samples previously collected throughout the Arctic to estimate grazing impact by mixotrophs in the polar ecosystem.
The researcher will join a team lead by Robert Sanders (Temple University) and Rebecca Gast (Woods Hole Oceanographic Institution), and will work with Arctic cultures in laboratory-based experiments. Basic qualifications are a PhD in aquatic ecology, biological oceanography or a related field. Experience in protistan/ phytoplankton biology, including culturing, is expected. Previous training in molecular techniques and/or bioinformatics is highly preferred, but not required. The position will be based at Temple University in Philadelphia PA, but the researcher will also work closely with the Gast laboratory in Woods Hole MA. To apply please send an application letter, curriculum vitae and names of at least three professional references to Bob Sanders. Review of applications will begin immediately and continue until the position is filled. Temple University is an equal opportunity, equal access, affirmative action employer committed to achieving a diverse community (AA, EOE, m/f/d/v).
Collaborative Research: The ecological impact of mixotrophic algae in a changing Arctic marine climate. National Science Foundation, Arctic Natural Sciences. Co-PIs: R.J. Gast (Woods Hole Oceanographic Institution) and R.W. Sanders. 2016-2019.
Another 1st author paper for Sarah:
Princiotta, S.D. and R.W. Sanders. 2017. Heterotrophic and mixotrophic nanoflagellates in a mesotrophic lake: abundance and grazing impacts across season and depth. Limnology & Oceanography 62: 632-644.