| one publication added to basket [27451] | Physiological and cytological responses of the marine diatom Skeletonema costatum to 2,4-dichlorophenol
In: Aquatic Toxicology. Elsevier Science: Tokyo; New York; London; Amsterdam. ISSN 0166-445X; e-ISSN 1879-1514, more
|  |
| Keywords |
Algae > Diatoms
Chemical compounds > Organic compounds > Carbohydrates > Glycosides > Pigments
Energy budget
Skeletonema costatum (Greville) Cleve, 1873 [WoRMS]
ANW, USA, Maine [Marine Regions]
Marine/Coastal |
| Authors | | Top |
- Yang, S.
- Wu, R.S.S.
- Kong, R.Y.C.
|
|
|
| Abstract |
Physiological and cytological responses of the marine diatom, Skeletonema costatum, to 2,4-dichlorophenol (2,4-DCP) were investigated after exposing algal cultures to 1-6 mg-1 of 2,4-DCP for 96 h. Growth rate of the diatom was significantly reduced by 2,4-DCP at and above 3.0 mg-1 while other biological parameters such as photosynthetic and respiration rates, carotenoid and protein content, ATP level and adenylate energy charge were unaffected. Exposure to 6.0 mg-1 2,4-DCP for 96 h resulted in the total lipid content being increased to 304%, while the RNA/DNA ratio was reduced to 31% of the control values. A parallel study by transmission electron microscopy further confirmed the increase in cellular lipid content, as evidenced by the accumulation of lipid droplets within diatom cells. A slight increase in carbohydrate (+37.8%) and decrease in chlorophyll a (20.4%) and total chlorophyll c (14.4%) were also found at 6.0 mg-1 2,4-DCP. Although 2,4-DCP is known to uncouple oxidative phosphorylation, our results show that energy production was not significantly inhibited at sublethal concentrations of 2,4-DCP. The observed growth inhibition in S. costatum caused by 2,4-DCP was associated with an increase in energy storage and inhibition of protein synthesis, as indicated by a reduction in RNA/DNA ratio. |
|
