Algae unicellular

The biflagellate unicellular green alga Chlamydomonas reinhardtii is prone to spontaneous mutations that produce deficiencies in flagellar proteins and MT assembly, substructure, and function. Viable mutants that are either nonmotile or slow moving can be isolated and analyzed biochemically and morphologically, thereby establishing structure-function correlations. Electron microscopic analysis... 

P aerugineum is a unicellular alga cultured under artificial or solar light in a freshwater medium supplied with CO2, in an outdoor bioreactor developed by Arad and Yaron. Algal growth was optimized for yield and for the properties of the blue color produced. The parameters that require close monitoring are light intensity and temperature, in order to avoid stress conditions that result in decreased color yield and solubility and increased biosynthesis of the polysaccharides that encapsulate the cells and are excreted into the medium. 

Blue Algae, such as cyanophyta, appear as unicellular threads they have a typical blue colour and they are able to bind elementary nitrogen. 

Two studies have used single cells to study the effect of phenolic acids on mineral absorption. In sterile cell cultures of Paul s Scarlet rose, 100 pM ferulic acid inhibited Rb+ absorption in about 10 min when the cells were 4-5 days old (37). Uptake from 0.2 mM RbCl was inhibited about 25% and absorption from 5.0 mM RbCl was inhibited 45%. Absorption by 10-day-old cells was affected little. Salicylic acid at 10 pM inhibited PO - absorption by Scenedesmus, a unicellular green alga (38). These studies show that allelochemicals inhibit mineral absorption in cellular systems as well as tissue systems (Table I). 

M Diatoms constitute a family of unicellular microscopic algae whose cell walls consist of two boxlike parts which contain silica. They are an important source of food for all kinds of marine organisms. 

Schafer, H., H. Hettler, U. Fritsche, G. Pitzen, G. Roderer, and A. Wenzel. 1994. Biotests using unicellular algae and ciliates for predicting long-term effects of toxicants. Ecotoxicol. Environ. Safety 27 64-81. 

El-Sheekh, M.M., H.M. Kotkat, and O.H.E. Hammouda. 1994. Effect of atrazine herbicide on growth, photosynthesis, protein synthesis, and fatty acid composition in the unicellular green alga Chlorella kessleri. Ecotoxicol. Environ. Safety 29 349-358. 

Hollister, T.A., G.E. Walsh, and J. Forester. 1975. Mirex and marine unicellular algae accumulation, population growth and oxygen evaluation. Bull. Environ. Contam. Toxicol. 14 753-759. 

Bottino, N.R., R.D. Newman, E.R. Cox, R. Stockton, M. Hoban, R.A. Zingaro, and K.J. Irgolic. 1978. The effects of arsenate and arsenite on the growth and morphology of the marine unicellular algae Tetraselmis chui (Chlorophyta) and Hymenomonas carterae (Chrysophyta). Jour. Exp. Mar. Biol. Ecol. 33 153-168. 

Boisson, F., M. Gnassia-Barelli, and M. Romeo. 1995. Toxicity and accumulation of selenite and selenate in the unicellular marine algae Cricosphaera elongata. Arch. Environ. Contamin. Toxicol. 28 497-493. Bovee, E.C. and T.L. O Brien. 1982. Some effects of selenium, vanadium and zirconium on the swimming rate of Tetrahymena pyriformis a bioassay study. Univ. Kans. Sci. Bull. 52 (4) 39 44. 

Disch, A., Schwender, J., Muller, C., Lichtenthaler, H.K., and Rohmer, M., Distribution of the mevalonate and glyceraldehyde phosphate/pyruvate pathways for isoprenoid biosynthesis in unicellular algae and the cyanobacterium Synechocystis PCC 6714, Biochem.., 333, 381, 1998. 

M. Winkler, B. Heil, T. Happe (2002) Isolation and molecular characterization of the [Fe]-hydrogenase from the unicellular green alga Chlorella fiisca. Biochem. Biophys. Acta, 1576 330-334... 

Fe]-hydrogenase from the unicellular green alga Chlorella fusca. Biochim. Biohys. Acta, 1576 330-334... 

Errecalde, O., Seidl, M. and Campbell, P. G. C. (1998). Influence of a low molecular weight metabolite (citrate) on the toxicity of cadmium and zinc to the unicellular green alga Selenastrum capricornutum an exception to the free-ion model, Water Res., 32, 419 -29. 

Sunda, W. G. and Huntsman, S. A. (1985). Regulation of cellular manganese and manganese transport rates in the unicellular alga Chlamydomonas, Limnol. Ocea-nogr., 30, 71-80. 

Diatoms are microscopic unicellular algae, with siliceous cell walls and the power of locomotion. 

One role of cyanobacterial allelochemicals may be to alter the motility and distribution of competing photoautotrophs. In a recent study, Kearns and Hunter (2001) examined the effects of toxic metabolites from the filamentous cyanobacterium A. flos-aquae on a unicellular phytoplankton species, Chlamydomonas rein-hardtii. A. flos-aquae synthesizes both microcystins as well as anatoxins, providing the authors with an ecologically relevant opportunity to assess the individual and combinatorial effects of these toxins on an alga. 

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