Sallie (Penny) W. Chisholm

Sallie (Penny) W. Chisholm

Institute Professor

Sallie (Penny) W. Chisholm studies the biology, ecology, and evolution of the single most abundant marine phytoplankton species in order to understand the forces that shape microbial ecosystems.





Tyler Sousa



Assistant Phone


  • PhD, 1974, SUNY Albany

Research Summary

Our goal is to understand the ecology and evolution of ocean microbes and how they influence global biogeochemical cycles. We focus on the cyanobacterium Prochlorococcus, which is the smallest and most abundant microbe in ocean ecosystems — sometimes accounting for half the total photosynthetic biomass. We use this model system to study life across all scales — from the genome to the ecosystem.


  • Crafoord Prize, 2019
  • Generalitat of Catalonia, Ramon Margalef Prize in Ecology, 2013
  • American Association for the Advancement of Science, Fellow, 2012
  • National Medal of Science, 2011
  • National Academy of Sciences, Alexander Agassiz Medal, 2010
  • National Academy of Sciences, Member, 2003
  • John Simon Guggenheim Memorial Foundation, Guggenheim Fellowship, 1997
  • American Academy of Arts and Sciences, Fellow, 1992

Key Publications

Recent Publications

  1. Environmental and Taxonomic Drivers of Bacterial Extracellular Vesicle Production in Marine Ecosystems. Biller, SJ, Coe, A, Arellano, AA, Dooley, K, Silvestri, SM, Gong, JS, Yeager, EA, Becker, JW, Chisholm, SW. 2023. Appl Environ Microbiol , e0059423.
    doi: 10.1128/aem.00594-23PMID:37199672
  2. Chitin utilization by marine picocyanobacteria and the evolution of a planktonic lifestyle. Capovilla, G, Braakman, R, Fournier, GP, Hackl, T, Schwartzman, J, Lu, X, Yelton, A, Longnecker, K, Soule, MCK, Thomas, E et al.. 2023. Proc Natl Acad Sci U S A 120, e2213271120.
    doi: 10.1073/pnas.2213271120PMID:37159478
  3. Draft genomes of three closely related low light-adapted Prochlorococcus. Berta-Thompson, JW, Thomas, E, Cubillos-Ruiz, A, Hackl, T, Becker, JW, Coe, A, Biller, SJ, Berube, PM, Chisholm, SW. 2023. BMC Genom Data 24, 11.
    doi: 10.1186/s12863-022-01103-4PMID:36829130
  4. Novel integrative elements and genomic plasticity in ocean ecosystems. Hackl, T, Laurenceau, R, Ankenbrand, MJ, Bliem, C, Cariani, Z, Thomas, E, Dooley, KD, Arellano, AA, Hogle, SL, Berube, P et al.. 2023. Cell 186, 47-62.e16.
    doi: 10.1016/j.cell.2022.12.006PMID:36608657
  5. Filter Plating Method for Rendering Picocyanobacteria Cultures Free of Heterotrophic Bacterial Contaminants and Clonal. Kearney, SM, Coe, A, Castro, KG, Chisholm, SW. 2022. Front Microbiol 13, 821803.
    doi: 10.3389/fmicb.2022.821803PMID:35250937
  6. Siderophores as an iron source for picocyanobacteria in deep chlorophyll maximum layers of the oligotrophic ocean. Hogle, SL, Hackl, T, Bundy, RM, Park, J, Satinsky, B, Hiltunen, T, Biller, S, Berube, PM, Chisholm, SW. 2022. ISME J 16, 1636-1646.
    doi: 10.1038/s41396-022-01215-wPMID:35241788
  7. Prochlorococcus extracellular vesicles: molecular composition and adsorption to diverse microbes. Biller, SJ, Lundeen, RA, Hmelo, LR, Becker, KW, Arellano, AA, Dooley, K, Heal, KR, Carlson, LT, Van Mooy, BAS, Ingalls, AE et al.. 2022. Environ Microbiol 24, 420-435.
    doi: 10.1111/1462-2920.15834PMID:34766712
  8. Coping with darkness: The adaptive response of marine picocyanobacteria to repeated light energy deprivation. Coe, A, Biller, SJ, Thomas, E, Boulias, K, Bliem, C, Arellano, A, Dooley, K, Rasmussen, AN, LeGault, K, O'Keefe, TJ et al.. 2021. Limnol Oceanogr 66, 3300-3312.
    doi: 10.1002/lno.11880PMID:34690365
  9. Microbial diversity of co-occurring heterotrophs in cultures of marine picocyanobacteria. Kearney, SM, Thomas, E, Coe, A, Chisholm, SW. 2021. Environ Microbiome 16, 1.
    doi: 10.1186/s40793-020-00370-xPMID:33902739
  10. Toward a genetic system in the marine cyanobacterium Prochlorococcus. Laurenceau, R, Bliem, C, Osburne, MS, Becker, JW, Biller, SJ, Cubillos-Ruiz, A, Chisholm, SW. 2020. Access Microbiol 2, acmi000107.
    doi: 10.1099/acmi.0.000107PMID:33005871
More Publications







Photo credit: Richard Howard