Influence of organic ligands on the toxicity of copper to Pseudomonas syringae

• Type: Article in International Scientific Journal
• Date: 1994

Authors

cabral, jps (Author) FCUP

Journal

Title: FEMS Microbiology Letters

Vol. 117

Pages: 341-344

ISSN: 0378-1097

Publisher: Oxford University Press

Indexing

ISI Web of Knowledge - 3 Citations

Scopus - 0 Citations

Scientific classification

FOS: Natural sciences > Biological sciences

Other information

Authenticus ID: P-00Q-ACG

DOI: 10.1111/j.1574-6968.1994.tb06789.x

Abstract (EN): Pseudomonas syringae cells were exposed to Cu2+ alone or in the precence of acetate, proline or cysteine, at concentrations that reduced free Cu2+ to 1/10 of the total copper. Ligand concentrations (designated as isoeffective) were determined experimentally using a Cu2+-selective electrode and confirmed by computer calculations using published stability constants. Exposure of P. syringae cells to Cu2+ alone resulted in rapid and pronounced cell death, and binding of most of the copper in solution. The addition of acetate, proline or cysteine, a few minutes after Cu2+ treatment, resulted in a significant reduction in cell death, and in the amount of copper bound to the cells. For short exposures to Cu2+, cysteine was more effective than acetate or proline, but after 60 min of treatment, similar results were observed with these ligands. The addition of ligands before Cu2+ resulted in even more reduced copper toxicity. The results showed that, at isoeffective concentrations, weak and moderate copper-ligands can effectively antagonize copper toxicity, and that this protective effect does not require previously equilibrated copper-ligand solutions and is not very dependent of the nature of the ligand. © 1994.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 4