Three-Dimensional Ultrastructural Study of Oil and Astaxanthin Accumulation during Encystment in the Green Alga Haematococcus pluvialis

• DOI: 10.1371/journal.pone.0053618
• Publication Date: 2013-01-12T00:01:23Z
• Authors: Marina Wayama; Shuhei Ota; Hazuki Matsuura; Nobuhito Nango; Aiko Hirata; Shigeyuki Kawano
• Keywords: Pyrenoid; Lipid droplet

Haematococcus pluvialis is a freshwater species of green algae and well known for its accumulation the strong antioxidant astaxanthin, which used in aquaculture, various pharmaceuticals, cosmetics. High levels astaxanthin are present cysts, rapidly accumulate when environmental conditions become unfavorable normal cell growth. It not understood, however, how high soluble oil, becomes possible during encystment. Here, we performed ultrastructural 3D reconstruction based on over 350 serial sections per to visualize dynamics subcellular changes encystment H. pluvialis. This study showcases marked elements, such as chloroplast degeneration, transition from coccoid cells red cyst In cells, chloroplasts accounted 41.7% total volume, whereas relative volume was very low (0.2%). contrast, oil droplets containing predominated (52.2%), markedly decreased (9.7%). Volumetric observations also demonstrated that volumes wall, starch grains, pyrenoids, mitochondria, Golgi apparatus, nucleus smaller than those coccid cells. Our data indicated degraded, resulting net-like morphology, but do completely disappear, even at stage.