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Induction of stress proteins in Isochrysis galbana exposed to crude oil and chemically dispersed crude oil preparation
Abstracts
405
&cu.s~ata) collected from five locations along the area affected by the oil spill. Samples were taken quarterly during one year. Molecular markers, such as sterane and terpane distributions or the presence of an unresolved complex mixture (UCM) in the hydrocarbons fraction, indicated the presence of the oil in the tissue of the organisms, even one year after the accident. Levels of whole body polycyclic aromatic hydrocarbons (PAHs) and alkylated PAHs showed qualitative and quantitative differences among the organisms and the sampling stations. Total PAHs in mussels collected one year after the oil spill ranged from 106 rig/g dry weight in the reference site to 565 rig/g in the area closest to the accident. Clams and cockles showed similar concentrations of PAHs, but different bioaccumulation patterns. Various biochemical measurements included MFO antioxidant enzymes (superoxide dismutase and DT-diaphorase) and glutathione S-transferase, all in the same organisms. Lipid peroxides were measured in mussel digestive gland as an index of damage caused by the oil spill. Superoxide dismutase activity and lipid peroxides content increased over time in all the organisms, possibly indicating enhanced oxidative stress as a result of the oil exposure. Total cytochrome P450, ‘41%peak’ and NADPH-cytochrome c(P450) reductase activity appear to decrease over time in mussels, and no significant change or even the opposite trend was detected in clams and cockles. Glutathione S-transferase activity varied considerably between species. Cockles and clams showed 2- and IO-fold higher activity than mussels, respectively. The results point out the importance of a multidisciplinary approach to build a more comprehensive picture of oil pollution and responses in marine bivalves.
Induction of Stress Proteins in Zsochrysis gafbana Exposed to Crude Oil and Chemically Dispersed Crude Oil Preparation. M. F. WOLFE,” H. E. OLSEN’ & R. S. TJEERDEMA.” “Department of Chemistry and Biochemistry, University of California. Santa Cruz, California, USA; bITEH, University of California, Davis, California, USA.
The fate of petroleum hydrocarbons released in the marine environment during an oil spill may be altered by the use of chemical dispersing agents. Exposure to species at the airwater interface may be decreased yet little is understood of the disposition of the dispersed components moving into the water column. The objective of this research was to examine sub-lethal endpoints in organisms exposed to crude oil and water preparations, with and without the application of dispersant. HSP-60 was selected as a sublethal endpoint for Zsochrysis galbana cultures exposed to water-accommodated fractions (WAF) of Prudhoe Bay Crude Oil (PBCO), Corexit@ 9527 alone, and PBCO/dispersant preparations. HSP60 proteins, members of the chaperonin family of stress proteins, are induced in response to a wide variety of environmental agents including UV light, heavy metals, and xenobiotics. These proteins are found in mitochondria and chloroplasts of eukaryotes and facilitate folding and assembly of proteins. Western blotting techniques using HSP-60 protein specific antibodies, were used to isolate and identify induced HSP-60 in I. galbana. Studies indicated that WAF produced a dose-related response in I. galbana, which increased as a function of time. Dispersant alone showed the greatest induction, producing a double band, while combined WAFdispersant showed less induction, suggesting a possible competition between crude oil and algae for dispersant interaction. Results showed that HSP-60 protein synthesis was induced in I. galbana in response to exposure to WAF, dispersant, and WAF-dispersant preparations.
405
&cu.s~ata) collected from five locations along the area affected by the oil spill. Samples were taken quarterly during one year. Molecular markers, such as sterane and terpane distributions or the presence of an unresolved complex mixture (UCM) in the hydrocarbons fraction, indicated the presence of the oil in the tissue of the organisms, even one year after the accident. Levels of whole body polycyclic aromatic hydrocarbons (PAHs) and alkylated PAHs showed qualitative and quantitative differences among the organisms and the sampling stations. Total PAHs in mussels collected one year after the oil spill ranged from 106 rig/g dry weight in the reference site to 565 rig/g in the area closest to the accident. Clams and cockles showed similar concentrations of PAHs, but different bioaccumulation patterns. Various biochemical measurements included MFO antioxidant enzymes (superoxide dismutase and DT-diaphorase) and glutathione S-transferase, all in the same organisms. Lipid peroxides were measured in mussel digestive gland as an index of damage caused by the oil spill. Superoxide dismutase activity and lipid peroxides content increased over time in all the organisms, possibly indicating enhanced oxidative stress as a result of the oil exposure. Total cytochrome P450, ‘41%peak’ and NADPH-cytochrome c(P450) reductase activity appear to decrease over time in mussels, and no significant change or even the opposite trend was detected in clams and cockles. Glutathione S-transferase activity varied considerably between species. Cockles and clams showed 2- and IO-fold higher activity than mussels, respectively. The results point out the importance of a multidisciplinary approach to build a more comprehensive picture of oil pollution and responses in marine bivalves.
Induction of Stress Proteins in Zsochrysis gafbana Exposed to Crude Oil and Chemically Dispersed Crude Oil Preparation. M. F. WOLFE,” H. E. OLSEN’ & R. S. TJEERDEMA.” “Department of Chemistry and Biochemistry, University of California. Santa Cruz, California, USA; bITEH, University of California, Davis, California, USA.
The fate of petroleum hydrocarbons released in the marine environment during an oil spill may be altered by the use of chemical dispersing agents. Exposure to species at the airwater interface may be decreased yet little is understood of the disposition of the dispersed components moving into the water column. The objective of this research was to examine sub-lethal endpoints in organisms exposed to crude oil and water preparations, with and without the application of dispersant. HSP-60 was selected as a sublethal endpoint for Zsochrysis galbana cultures exposed to water-accommodated fractions (WAF) of Prudhoe Bay Crude Oil (PBCO), Corexit@ 9527 alone, and PBCO/dispersant preparations. HSP60 proteins, members of the chaperonin family of stress proteins, are induced in response to a wide variety of environmental agents including UV light, heavy metals, and xenobiotics. These proteins are found in mitochondria and chloroplasts of eukaryotes and facilitate folding and assembly of proteins. Western blotting techniques using HSP-60 protein specific antibodies, were used to isolate and identify induced HSP-60 in I. galbana. Studies indicated that WAF produced a dose-related response in I. galbana, which increased as a function of time. Dispersant alone showed the greatest induction, producing a double band, while combined WAFdispersant showed less induction, suggesting a possible competition between crude oil and algae for dispersant interaction. Results showed that HSP-60 protein synthesis was induced in I. galbana in response to exposure to WAF, dispersant, and WAF-dispersant preparations.