 Two strains of gram-positive bacteria have been discovered that can tolerate high concentrations of arsenic in their environment. These strains, named SW2 and SW4, can reduce the levels of both arsenate and arsenide in contaminated water by up to 53%. Furthermore, these strains can convert arsenide into less harmful arsenate, making them ideal candidates for use in bioremediation processes. This article was authored by Atiyah Day, Simondranath Chatterjee and Naba Kumar, Mondal.