BIOSORPTION OF COPPER(II) BY PSEUDOMONAS-AERUGINOSA

The mechanism of accumulation of copper(II) by Pseudomonas aeruginosa was investigated. Uptake consisted of a rapid process (likely to be ex tracellular binding) followed by a slow phase (possibly cellular uptak e). The sorption capacity of the microbe was found to be 50 mg/g, and sorption followed the Langmuir isotherm. The presence of mild mineral acids (0.1 N HCl) led to destructive desorption of 95% of sorbed metal , whereas citrate buffer (pH 4) desorbed 80% of the accumulated metal ions non-destructively. Spectroscopic and microscopic studies indicate d the accumulation of metal inside the cell, though the maximum uptake was by the cell wall.