A new picoeukaryote: Nannochloropsis sp. DP001- ultrastructure, pigmentation, heterotrophic growth and phylogeny

• Main Authors: Tai-Chih Wu, 吳岱芝
• Other Authors: Kwee-Siong Tew
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/39498373888186515624

碩士 === 國立東華大學 === 海洋生物多樣性及演化研究所 === 99 === Picophytoplankton (0.2 ~ 2.0 μm) can be found in the ocean all over the world, and picoeukaryotes are the smallest photosynthetic organisms found to date. In the last 15 years, only about 80 species of picoeukaryotes have been identified. The strain we studied was isolated from a highly polluted lagoon. Based on the 18S rDNA gene sequence, the organism affiliates to the phylum Heterokontophyta, class Eustigmatophyceae, genus Nannochloropsis. The cell consists of one nucleus, one golgi body, one or two mitochondria, one or two chloroplasts, one or two pyrenoids and plastoglobulis within the chloroplast. The strain grows to stationary phase in 10 days under f/2 medium, 24℃ with 12：12 light：dark cycle, and under 100 μmol photons m-2s-1. Pigment analysis reveals that chlorophyl a, violaxanthin, β-carotene and vaucheriaxanthin are the main pigments. Under heterotrophic condition, medium with fructose and maltose respectively provides rapid growth as compare to the control and glucose medium, revealed that the strain can grow well without light as long as suitable organic compounds are provided.