People

PEOPLE IN THE BHAYA AND GROSSMAN LABORATORIES

Claudia Catalanotti: Postdoctoral fellow working on the acclimation of photosynthetic organisms to anoxia.

David Dewez: Postdoctoral fellow working on photosynthetic genes and their function and evolution.

 Rosario Garcia-Gomez (left): Postdoctoral fellow working with the Bhaya and Grossman groups on the ways in which hot spring organisms utilize nutrients.

David Gonzalez-Ballester: Postdoctoral fellow who recently accepted a position in Spain and who worked on the acclimation of Chlamydomonas to sulfur deprivation.

Blaise Hamel: Graduate student working on proteins of unknown function associated with the green lineage and potentially with chloroplast/photosynthetic function.

Mark Heinnickel: Postdoctoral fellow working on the function of genes in the green lineage (associated with photosynthetic function)

Danielle Ikoma: Undergraduate working on screens to identify specific mutants in Chlamydomonas.

Sheila Jensen: Visiting graduate student from Michael Kühl’s laboratory in Denmark working on the diel cycling of carbon in the hot springs with both Grossman and Bhaya.

 Leonardo Magneschi: Visiting graduate student working on anoxic responses in photosynthetic organisms.

Kate Mackey: Former graduate student who worked in collaboration with Adina Payton on photosynthesis and acclimation of phytoplankton in the oceans.
 

Wirulda Pootakham:  Graduate student working on the sulfate transporters and their regulation in algae.
 

Eva Nowack: Working on the evolution of the chloroplast using Paulinella chromatophora as a model system.

Dimitri Tolleter obtained his Ph.D. from the University of Angers (France) in 2007 under the guidance of David Macherel. His Ph.D. project focused on desiccation processes and structural and functional characterizations of a LEA (Late Embryogenesis Abundant) protein in the model plant Pisum sativum. He then went to Gilles Peltier’s laboratory where he worked on cyclic electron flow and hydrogen production in Chlamydomonas. This experience with photosynthesis has allowed him to contribute significantly to the analysis of photosynthesis in the dinoflagellate Symbiodinium, an alga that lives inside the tissue of corals (animals; cnidarians) as an endosymbiont; the algae provide the corals with fixed carbon, which is critical for their survival. Dr. Tolleter has recently demonstrated that temperature-induced coral bleaching can be as severe in the dark as in the light (in the absence of photosynthetically produced reactive oxygen species). Almost all previous hypotheses concerning coral bleaching has attributed the bleaching to the photosynthetic production of reactive oxygen species. Furthermore, heat elicited damage to the photosynthetic apparatus can also occur in the dark. These findings are helping us elucidate the events and mechanisms associated with the bleaching of coral reefs. New data on the ways that environmental change impact gene expression in Symbiodinium can be found here.

Tingting Xiang obtained her Ph.D. from National Institute of Biological Sciences (Beijing, China) in 2010. Her thesis project focused on mechanisms by which pathogenic bacteria cause plant disease responses. She was then attracted to studies of the coral (cnidarian)-dinoflagellate (Symbiodinium) symbiosis and joined the Grossman Laboratory to participate in a collaborative project involving the laboratories of Arthur Grossman, John Pringle and Steve Palumbi. These groups have developed ways to generate axenic cultures of Symbodinium, examine responses of corals to environmental change in field and laboratory samples, and established a laboratory-based proxy system to dissect coral bleaching and both temperature and light responses of the cnidarian-dinoflagellate association in a controlled laboratory setting. For the proxy system, John Pringle’s group extended on previous work in which the dinoflagellate Symbiodinium was introduced into a clonal population of the small sea anemone Aiptasia pallida (this organism is a cnidarian like the coral and can also be populated by Symbiodinium). Recently some of this work was published in the Journal of Phycology (Xiang et al., 2013). Using this Aiptasia-Symbiodinium model system, the groups are dissecting the physiology, cellular and molecular biology of the cnidarian-dinoflagellate mutualism, with an emphasis on elucidating mechanisms associated with the bleaching response. New data on the ways that environmental change impact gene expression in Symbiodinium can be found here.

 

Wenqiang Yang: Generating strains of Chlamydomonas with mutations in the various pathways of fermentation metabolism and dissection the way the lesions impact overall metabolism.