, Volume 57, Issue 3, pp 127–132 | Cite as

The kleptoplastic sea slug Elysia clarki prolongs photosynthesis by synthesizing chlorophyll a and b

  • Michael L. Middlebrooks
  • Susan S. Bell
  • Sidney K. Pierce


Several species of kleptoplastic, sacoglossan sea slug photosynthesize using chloroplasts sequestered inside their digestive cells from algal food sources. However, sequestered chloroplasts alone are not sufficient for months-long, continuous photosynthesis and maintenance of the chloroplasts in absence of the algal nucleus. Some type of plastid maintenance mechanism must be present to help sustain photosynthetic activity in the long term kleptoplastic species, such as Elysia clarki. We demonstrate that E. clarki starved for 2 weeks are able to synthesize chlorophylls, but that slugs starved for 14 weeks no longer synthesize chlorophyll. The subsidence of chlorophyll synthesis is coincident with the cessation of photosynthesis by the starved slugs, but it is not yet known if the cessation of pigment synthesis is the cause or some other aspect of plastid degradation produces a loss of synthetic ability.


Sacoglossan Kleptoplasty Chlorophyll synthesis Animal photosynthesis 



We would like to thank Julie Schwartz for help in preparing samples and running the HPLC. We thank a private donor, who wishes to remain anonymous, for financial support.


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Copyright information

© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  • Michael L. Middlebrooks
    • 1
  • Susan S. Bell
    • 1
  • Sidney K. Pierce
    • 1
  1. 1.Department of Integrative BiologyUniversity of South FloridaTampaUSA

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