| Summary: | Sustainable mechanisms for efficient and circular metal recycling have yet to be uncovered. In this study, the metal recycling potential of seven metal-resistant bacterial species (<i>Deinococcus radiodurans</i>, <i>Deinococcus aerius</i>, <i>Bacillus coagulans</i>, <i>Pseudomonas putida</i>, <i>Staphylococcus rimosus</i>, <i>Streptomyces xylosus</i> and <i>Acidocella aluminiidurans</i>) was investigated in a multi-step strategy, which comprises bioleaching of industrial waste products and subsequent biosorption/bioaccumulation studies. Each species was subjected to an acidic, multi-metal bioleachate solution and screened for potential experimental implementation. Bacterial growth and metal acquisition were examined using scanning transmission electron microscopy coupled to electron dispersive X-ray spectroscopy (STEM-EDS). Two of the seven screened species, <i>D. aerius</i> and <i>A. aluminiidurans</i>, propagated in a highly acidic and metal-laden environment. Both accumulated iron and copper compounds during cultivation on a multi-metallic bioleachate. Our findings suggest that extremotolerant bacteria should be considered for waste recycling operations due to their inherent polyextremophily. Furthermore, STEM-EDS is a promising tool to investigate microbial–metal interactions in the frames of native industrial waste products. To develop further experimental steps, detailed analyses of adsorption/accumulation mechanisms in <i>D. aerius</i> and <i>A. aluminiidurans</i> are required to design a circular metal recycling procedure.
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