Poster: Organelle Biogenesis

Abs # 1160: Comparative Robustness of isolated chloroplasts from pea and the alga Codium fragile.

Presenter:	Archer, Kathleen , kathleen.archer@trincoll.edu
Authors	Archer, Kathleen  (A)   Winnicka, Beata  (A)
Affiliations:	(A): Trinity College

Isolated chloroplasts from higher plants can photosynthesize and translate proteins for at least several hours after isolation, but they typically do not retain high function for more than a day. Chloroplasts from certain siphonous algae, however, are isolated by sea slugs during feeding and taken up into the animal's cells where they survive in a functional state for up to 9 months. The ability to tolerate the conditions of the digestive tract and subsequently to persist in the cellular environment of the slug is remarkable, and suggests that these algal chloroplasts may be more rugged than higher plant chloroplasts. We decided to test chloroplast robustness by comparing isolated chloroplasts from Pisum sativum (garden pea) and Codium fragile. Codium is a widely distributed siphonous green alga used by the slug Elysia viridis as a source of chloroplasts. We are using the ferricyanide-dependent oxygen evolution method to assess chloroplast intactness after exposure to a range of pH treatments and digestive enzymes. Preliminary experiments indicate a tolerance in both pea and Codium chloroplasts for alkaline pHs as high as 11. Further experiments are in progress.