The concept of light intensity adaptation in marine phytoplankton: some experiments with Phaeodactylum tricornutum

1977 ◽  
Vol 24 (4) ◽  
pp. 256
Keyword(s):  
Light Intensity ◽  
Phaeodactylum Tricornutum ◽  
Marine Phytoplankton

scholarly journals SPX-related genes regulate phosphorus homeostasis in the marine phytoplankton, Phaeodactylum tricornutum

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Kaidian Zhang ◽  
Zhi Zhou ◽  
Jiashun Li ◽  
Jingtian Wang ◽  
Liying Yu ◽  
...  
Keyword(s):  
Stress Responses ◽  
Phaeodactylum Tricornutum ◽  
Response Regulator ◽  
P Uptake ◽  
Negative Regulator ◽  
Marine Phytoplankton ◽  
Alkaline Phosphatases ◽  
Phosphate Starvation Response ◽  
Essential Nutrient ◽  
Global Oceans

AbstractPhosphorus (P) is an essential nutrient for marine phytoplankton. Maintaining intracellular P homeostasis against environmental P variability is critical for phytoplankton, but how they achieve this is poorly understood. Here we identify a SPX gene and investigate its role in Phaeodactylum tricornutum. SPX knockout led to significant increases in the expression of phosphate transporters, alkaline phosphatases (the P acquisition machinery) and phospholipid hydrolases (a mechanism to reduce P demand). These demonstrate that SPX is a negative regulator of both P uptake and P-stress responses. Furthermore, we show that SPX regulation of P uptake and metabolism involves a phosphate starvation response regulator (PHR) as an intermediate. Additionally, we find the SPX related genes exist and operate across the phytoplankton phylogenetic spectrum and in the global oceans, indicating its universal importance in marine phytoplankton. This study lays a foundation for better understanding phytoplankton adaptation to P variability in the future changing oceans.

scholarly journals Phaeodactylum Trıcornutum Kültürlerinde Biyomas Tahmini

2017 ◽  
Vol 5 (2) ◽  
pp. 182
Author(s):  
Burcu Ak ◽  
Gökhan Tamer Kayaalp ◽  
Oya Işık ◽  
Melis Çelik Güney
Keyword(s):  
Light Intensity ◽  
Chlorophyll A ◽  
Optical Density ◽  
Phaeodactylum Tricornutum ◽  
Dry Matter ◽  
Nitrogen Deficiency ◽  
Regression Equation ◽  
Control Group ◽  
Analysis Method ◽  
The Mathematical Model

Phaeodactylum tricornutum is the microalgae that is known to produce lipid. In this study, it was aimed to estimate the microalgae Phaeodactylum tricornutum dry matter cultured in the conditions of nitrogen deficiency as a stress factor, in outdoor, in photo bioreactors, by using multiple regression analysis method. In this study, diatom Phaeodactylum tricornutum (Bohlin) was cultured medium of which N was reduced by 50% and with 20% inoculation ratio. The light intensity, temperature, optical density and chlorophyll a, were measured daily. The mathematical model was formed for control group and 50 % of the N applied to the group using optical density, temperature, light intensity, chlorophyll a and without chlorophyll a. The regression equation of control group was estimated. The R2 value of control group was found 95.1% and statistically significant. Then, the regression equation was estimated for control group without chlorophyll a. The R2 value of this equation was found 94.0% and statistically significant. And then, the regression equation was estimated in 50% nitrogen. The R2 value of control group was found 92.4% and statistically significant. Finally, the regression equation was estimated in 50% nitrogen deficiency without chlorophyll a. The R2 value of this equation was found 91.7% and statistically significant.

Studies on the growth of Phaeodactylum tricornutum III. The effect of iron on growth

1968 ◽  
Vol 48 (2) ◽  
pp. 295-302 ◽  
Author(s):  
J. Hayward
Keyword(s):  
Iron Deficiency ◽  
Iron Content ◽  
Phaeodactylum Tricornutum ◽  
Marine Phytoplankton ◽  
Iron Nutrition

The iron nutrition of Phaeodactylum tricornutum (Bohlin) has been studied, and the limitation of growth because of iron deficiency demonstrated. Evidence is presented suggesting the ability of the organism to utilize paniculate iron and to adjust its utilization of iron in the presence of a continuing deficiency. One effect of lack of iron is a reduction in the degree of pigmentation and the ability of added iron to restore the pigmentation. Figures are presented showing the iron content per cell, and a comparison with other organisms suggests that the brackishwater P. tricornutum may be atypical when compared with coastal and oceanic members of the marine phytoplankton.

The use of thin-layer chromatography for the separation and identification of phytoplankton pigments

1965 ◽  
Vol 45 (3) ◽  
pp. 583-591 ◽  
Author(s):  
J. P. Riley ◽  
T. R. S. Wilson
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Phaeodactylum Tricornutum ◽  
Isochrysis Galbana ◽  
Marine Phytoplankton ◽  
Rapid Separation ◽  
Systematic Classification ◽  
Layer Chromatography ◽  
Natural Phytoplankton

Thin-layer chromatography has been used for the rapid separation of microgram amounts of pigments of marine phytoplankton, both from cultures and from the sea. The separation is carried out on plates coated with silica gel; the chromatogram is developed with a solvent consisting of petroleum ether (b.p. 60–80°), ethyl acetate and diethylamine in the ratio 58:30:12 by volume. The separated individual pigments may be eluted from the plate and characterized by their absorption spectra. The pigments of the following phytoplankton have been examined: Dunaliella primolecta, Phaeodactylum tricornutum, Isochrysis galbana, Dicrateria inornata, Coccolithus huxleyi, and Peridinium trochoidium.IntroductionA knowledge of the component pigments of phytoplankton is of value in the systematic classification of these organisms and in the study of the mechanism of photosynthesis. Very little is known about the amounts of the lesser phyto-plankton pigments associated with the natural phytoplankton crop in the sea, but a considerable amount of work has been carried out on the measurement of chlorophylls a, b and c and of carotenoids for the estimation of the plant bio-mass in the sea. These determinations are usually carried out by modifications of the poly-chromatic spectrophotometric method originally described by Richards with Thompson (1952) and modified by Creitz & Richards (1955) (see also Parsons & Strickland, 1963). While these procedures give a satisfactory measure of chlorophylls a and b, their precision for chlorophyll c and carotenoids is poor; furthermore, no resolution of carotenes from xanthophylls can be attained; nor can any indication of the presence of unusual pigments be obtained.

scholarly journals Nutrient experiment using Phaeodactylum tricornutum as an assay organism

1976 ◽  
Vol 25 (1) ◽  
pp. 29-42 ◽  
Author(s):  
C. Teixeira ◽  
A. A. H. Vieira
Keyword(s):  
Coastal Waters ◽  
Phaeodactylum Tricornutum ◽  
Marine Phytoplankton ◽  
Phytoplankton Production ◽  
Limiting Factor ◽  
Carbon 14

The growth of Phaeodactylum tricornutum, cultured at 7,000 lux and 25º C, in twelve-day experiments using enriched water collected at the surface and 50.0 m depth from coastal waters offshore of Ubatuba area, was carried out. Different water enrichements were made by the aseptic addition of several nutrients, at each depth, according to Smayda (1964). The nitrogen out measured in terms of Carbon-14 assimilation and cloropyll concentration, was found to be a primary limiting factor for marine phytoplankton production.

Sign in / Sign up

Export Citation Format

Share Document