Search results for "Euglena"
showing 8 items of 8 documents
The light-harvesting system of Euglena gracilis during the cell cycle
1989
The apoproteins of the light-harvesting chlorophyll-protein complexes LHCI and CP29 (apparent molecular weights of 27 kDa and 29 kDa, respectively) of Euglena gracilis were identified immunologically. Both complexes are present in the thylakoids of autotrophically cultured Euglena cells during the whole cell cycle. The relative amount of each apoprotein tends to increase towards the end of the cell cycle. The light-harvesting chlorophyll-protein complex of photosystem II, LHCII, of E. gracilis contains chlorophyll a, chlorophyll b, neoxanthin, diadinoxanthin and beta-carotene. Its chlorophyll a/b ratio is about 1.7 during the whole cell cycle. About 9 h after cell division the ratio of diad…
Evidence for the Existence of a Pseudogene for the Large Subunit of Rubisco within the Chloroplast DNA of Norway Spruce (Picea Abies)
1998
Many hundreds of genes are involved in the synthesis, maintenance and degradation of chloroplasts. Although quite a number of these genes are located in the chloroplast genome, by far the greater proportion is present in the nuclear genome. The sizes of chloroplast DNAs (cpDNA) were estimated from restriction enzyme mapping studies and the complete sequences of different cpDNAs from diverse plant lineages have been determined to date (Marchantia polymorpha [1], Nicotiana tabacum [2], Oryza saliva [3], Epifagus virginiana [4], Euglena gracilis [5], Pinus thunbergii [6], Porphyra purpurea [7], Odontella sinensis [8], Zea mays [9], Chlorella vulgaris [10]).
Bioflocculation of Euglena gracilis via direct application of fungal filaments: a rapid harvesting method
2021
Funding Information: Special thanks to the US Agricultural Research Service for the provision of fungal strains. Thanks also to Dr Marilyn Wiebe (Technical Research Centre of Finland) for her expert advice on fungi and Johanna Oja for her technical help. This research was enabled by funding from The Land and Water Technology Foundation, The Finnish Cultural Foundation, and The Finnish Foundation for Technology Promotion. Publisher Copyright: © 2021, The Author(s). The high cost and environmental impact of traditional microalgal harvesting methods limit commercialization of microalgal biomass. Fungal bioflocculation of microalgae is a promising low-cost, eco-friendly method but the range of …
CORRELATED BIOCHEMICAL AND ULTRASTRUCTURAL CHANGES IN NITROGEN-STARVED EUGLENA GRACILIS1
1996
Growth of Euglena gracilis Z Pringsheim under photoheterotrophic conditions in a nitrogen-deprived medium resulted in progressive loss of chloroplastic material until total bleaching of the cells occurred. Biochemical analysis and ultrastructural observation of the first stages of the starvation process demonstrated an early lag phase (from 0 to 9 h) in which cells increased in size, followed by a period of cell division, apparently supported by the mobilization of some chloroplastic proteins such as the photosynthetic CO2-fixing enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase. The degradation of the enzyme started after 9 h of starvation and was preceded by a transient concentration…
Modification of the proteolytic fragmentation pattern upon oxidation of cysteines from ribulose 1,5-bisphosphate carboxylase/oxygenase.
2003
The proteolytic susceptibility of the native CO 2 -fixing photosynthetic enzyme ribulose 1,5-bisphosphate carboxylase/oxygenase (EC 4.1.1.39, Rubisco) has been shown to increase in vitro after oxidative treatments that affect cysteine thiols. A limited incubation of oxidized (pretreated with the disulfide cystamine) Rubisco from Chlamydomonas reinhardtii with subtilisin or proteinase K generated fragments of molecular mass about 53 kDa (band I in SDS-PAGE) and 47 kDa (band II) derived from the large subunit (55 kDa) of the enzyme. In contrast, proteolysis of the reduced Rubisco (pretreated with the free thiol cysteamine) produced only the 53 kDa band. The same fragmentation pattern was repr…
Oxidative modification and breakdown of ribulose-1,5-bisphosphate carboxylase/oxygenase induced in Euglena gracitis by nitrogen starvation
1994
When photoheterotrophic Euglena gracilis Z Pringsheim was subjected to nitrogen (N)-deprivation, the abundant photosynthetic enzyme ribulose-1,5-bis-phosphate carboxylase/oxygenase (Rubisco; EC 4.1.1.39) was rapidly and selectively degraded. The breakdown began after a 4-h lag period and continued for a further 8 h at a steady rate. After 12 h of starvation, when the amount of Rubisco was reduced to 40%, the proteolysis of this enzyme slowed down while degradation of other proteins started at a similar pace. This resulted in a decline of culture growth, chloroplast disassembly — as witnessed by chlorophyll (Chl) loss — and cell bleaching. Experiments with spectinomycin, an inhibitor of chlo…
Immunomodulatory effects of dietary β-1,3-glucan from Euglena gracilis in rainbow trout (Oncorhynchus mykiss) immersion vaccinated against Yersinia r…
2012
Abstract Potential immunostimulatory effects of orally administered β-glucan were investigated in combination with immersion vaccination against enteric redmouth disease caused by Yersinia ruckeri in rainbow trout (Oncorhynchus mykiss). A linear, unbranched and pure (purity ≥98%) β-1,3-glucan (syn. paramylon) from the alga Euglena gracilis was applied at an inclusion level of 1% β-glucan in feed administered at a rate of 1% biomass day−1 for 84 consecutive days. Fish were vaccinated after two weeks of experimental feeding and bath challenged with live Y. ruckeri six weeks post-vaccination. Blood and head kidney were sampled at day 0, 13 (1 day pre-vaccination), 15, 55, 59 (day 3 post-challe…
Data from: The importance of phytoplankton biomolecule availability for secondary production
2018
The growth and reproduction of animals is affected by their access to resources. In aquatic ecosystems, the availability of essential biomolecules for filter-feeding zooplankton depends greatly on phytoplankton. Here, we analyzed the biochemical composition, i.e., the fatty acid, sterol and amino acid profiles and concentrations as well as protein, carbon, nitrogen, and phosphorus content of 17 phytoplankton monocultures representing the seven most abundant phytoplankton classes in boreal and sub-arctic lakes. To examine how the differences in the biochemical composition between phytoplankton classes affect their nutritional quality for consumers, we assessed the performance of Daphnia, on …