Response of two terrestrial green microalgae (Chlorophyta, Trebouxiophyceae) isolated from Cu-rich and unpolluted soils to copper stress

Environ Pollut. 2010 Aug;158(8):2778-85. doi: 10.1016/j.envpol.2010.03.003. Epub 2010 Jun 3.

Abstract

Some algae inhabit Cu-polluted soils. Intracellular Cu-accumulation and production of non-protein thiols in response to copper stress were compared in Stichococcus minor and Geminella terricola isolated from Cu-polluted and unpolluted soils, respectively. Cu-exposed (0.5 microM) S. minor accumulated lower amounts of copper (0.38 mM) than G. terricola (4.20 mM) and maintained 8.5-fold higher level of glutathione (GSH) than G. terricola. The ratio GSH/0.5 GSSG in the Cu-treated S. minor (7.21) was 7-times higher than in G. terricola. Reduced and oxidized forms of phytochelatins were found in both algae. Under copper stress (5 microM) the ratio -SH(total)/Cu(intracellular) in S. minor ranged from 2.3 to 6.2, while it was lower than 1.0 in G. terricola. Low intracellular Cu-accumulation and maintenance of high GSH level concomitant with PCs production seem to be responsible for a higher Cu-resistance of S. minor than G. terricola.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chlorophyta / drug effects*
  • Chlorophyta / isolation & purification
  • Chlorophyta / metabolism
  • Copper / analysis
  • Copper / metabolism
  • Copper / toxicity*
  • Cysteine / metabolism
  • Dipeptides / metabolism
  • Glutathione / metabolism
  • Phytochelatins / metabolism
  • Soil Pollutants / analysis
  • Soil Pollutants / metabolism
  • Soil Pollutants / toxicity*

Substances

  • Dipeptides
  • Soil Pollutants
  • Copper
  • Phytochelatins
  • Glutathione
  • Cysteine
  • gamma-glutamylcysteine