Chromium binding Bacillus cereus VITSH1—a promising candidate for heavy metal clean up

Bacteria survive metal stress by several mechanisms and metal binding is one such mechanism which has been screened in the present study to investigate the survival strategies of metal resistant bacteria. The production of siderophores, a metal chelating agent, was detected by chrome azurol S agar assay. The changes in cell wall studied by analysing the peptidoglycan and teichoic acid content indicated an increase in the cell wall content. Evaluation of morphological and physiological alterations like cell size, granularity analysed by SEM and flow cytometry analysis revealed an increase in cell size and granularity respectively. The transformation of phosphates monitored by 31P NMR analysis indicated the presence of inorganic phosphate. Based on the cell wall changes and the 31P NMR analysis, the surface charge of the organism was studied by zeta potential which displayed a difference at pH7. Significance and Impact of the Study: Siderophore secretion, increase in cell wall components and the transformation of phosphates equip the metal‐resistant bacteria in several ways to cope with the stress condition and make them suitable for biotechnological applications. Application of this metal‐binding organism in environmental clean‐up strategies would fulfil the need for sustainable remediation technologies to restore the natural condition of the environment.