Green algae, arsenic

Matsuto, S., H. Kasuga, H. Okumoto, and A. Takahashi. 1984. Accumulation of arsenic in blue-green alga, Phormidium sp. Comp. Biochem. Physiol. 78C 377-382. 

Arsenic concentrations in marine algae are generally considerably higher in brown algae than in either red or green algae. Reasons... 

Kuroiwa, T., Ohki, A., Naka, K. and Maeda, S. (1994) Biomethylation and biotransformation of arsenic in a freshwater food chain green alga (Chlorella vulgaris) — shrimp (Neocaridina denticulata) — Killifish (Oryzias latipes). Appl. Organomet. Chem., 8, 325-333. 

Tables I to III provide a summary of some representative data for total arsenic concentrations in sediments, marine algae, and marine animals. There can be considerable variation in the arsenic levels in these samples, in contrast to the levels in seawater, which are reasonably uniform in the world s oceans at about 0.5-2 p.g/liter (9,10). For sediments, there is perhaps a tendency for arsenic concentrations to be lower in samples from coastal regions and estuaries compared with deep-sea sediments. Industrial discharges of arsenic-enriched effluents can, however, result in arsenic contamination of near-shore sediments (11,12). Arsenic concentrations in marine algae are generally considerably higher in brown algae than in either red or green algae. Reasons...

MD Baker, PTS Wong, YK Chau, Cl Mayfield, WE Inniss. Methylation of arsenic by freshwater green algae. Can J Fish Aquat Sci 40 1254-1257, 1983. 

The cessation of nitrate reduction on transfer of green algae to ammonium has been attributed to the uncoupling effect of this ion on noncyclic photo-phosphorylatim and a resultant increase in intracellular reducing power and ADP. Supporting this proposal are the findings that arsenate can duplicate the ammonium effect and the inactivation by anunonium ions can be prevented by treatment of cells with DCMU, an inhibitor of photosynthetic electron transfer (Losada, 1973, 1975 Chaparro et al., 1976). It has been demonstrated that ADP and/or NADH inactivate nitrate reductase in vitro... 

Maeda, S., Fujita, S., Ohki, A., Yoshifuku, I., Higashi, S., and Takeshita, T (1988). Arsenic accumulation by arsenic-tolerant freshwater blue-green alga Phormidium sp.) Appl Organomet. Chem., 2, 353-357. 

The presence of arsenic-containing sugars, however, is not specific to brown algae, as several of them have recently been identified in the green, red, and brown algae of the Adriatic Sea (Slejkovec et al, 2006). The broader presence of arsenic derivatives (arsenolipids, arsenobe-taine, arsenocholine) is also not limited to marine organisms for a major review on this subject, see Dembitsky and Levitsky (2004). 

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