Biotransformation of mercury in pH-stat cultures of eukaryotic freshwater algae |
| |
Authors: | David J A Kelly Kenneth Budd Daniel D Lefebvre |
| |
Institution: | (1) Department of Biology, Queen’s University, Kingston, ON, K7L 3N6, Canada |
| |
Abstract: | Eukaryotic algae were studied to determine their ability to biotransform HgII under aerated and pH controlled conditions. All algae converted HgII into β-HgS and Hg0 to varying degrees. When HgII was administered as HgCl2 to the algae, biotransformation by species of Chlorophyceae (Selenastrum
minutum and Chlorella fusca var. fusca) was initiated with β-HgS synthesis (K
1/2 of hours) and concomitant Hg° evolution occurred in the first hour. Hg° synthesis was impeded by the formation of β-HgS and
this inhibition was released in C. fusca var. fusca when cellular thiols were oxidized by the addition of dimethylfumarate (DMF). The diatom, Navicula pelliculosa (Bacillariophyceae), converted a substantially greater proportion of the applied HgII into Hg0, whereas the thermophilic alga, Galdieria sulphuraria (Cyanidiophyceae), rapidly biotransformed as much as 90% of applied HgII into β-HgS (K
1/2 ≈ 20 min). This thermophile was also able to generate Hg0 even after all exogenously applied HgCl2 had been biotransformed. The results suggest that β-HgS may be the major dietary mercurial for grazers of contaminated eukaryotic
algae. |
| |
Keywords: | Eukaryotic algae Metals Mercury sulfide Metacinnabar |
本文献已被 PubMed SpringerLink 等数据库收录! |
|