BIOREMEDIATION OF CADMIUM CONTAMINATED WATER: BACTERIAL ACCUMULATION AND SURFACE COMPLEXITY BY REVIBACILLUS AGRI C15 AND BREVIBACILLUS AGRI C15 CDR

Abstract

Brevibacillus agri C15 and Brevibacillus agri C15 CdR have been reported as a tool for do uptake of cadmium (Cd). Nevertheless, it is unclear whether these strains contrast in their adsorption behaviors and surface complexation could be one of the possible mechanisms that occurred. Therefore, this research aimed to investigate the mechanisms of cadmium uptake by B. agri C15 and B.agri C15 CdR in batch cultures and under TEM detection based on the maximum ATP or NADH production to energy metabolism using a resting cell experiment. In addition, surface complexation of cadmium in strains was studied. The results showed that the accumulation of Cd under TEM detection predicts that Cd bioaccumulation is the main mechanism in B. agri C15 and that adsorption is the main mechanism in B.agri C15 CdR. The observation of vesicles and granules, mainly poly-β-hydroxybutyrate under Cd-sublethal concentration may contribute to the adsorption and intercellular sequestration of Cd. There were differences in the cell compartments through the uptake process of Cd by the bacterial cells and the examinations of the contribution of surface complexation mechanisms in the uptake of Cd were obtained. Therefore, determining the thermodynamic stability constants of both strains from the available obtained parameters from this study was necessary.

Keywords

• atp
• brevibacillus agri
• cadmium
• nadh
• surface complexation