Phys.org  March 24, 2020 Researchers at the university of Colorado have demonstrated that the morphology and nanomechanical properties of calcium carbonate (CaCO3) can be tailored by modulating the precipitation kinetics of ureolytic microorganisms through genetic engineering. They hypothesized that microorganisms genetically engineered for low urease activity would achieve larger calcite crystals with higher moduli. They compared precipitation kinetics, morphology, and nanomechanical properties for biogenic CaCO3 produced by two Escherichia coli (E. coli). Both calcite crystal size and nanoindentation moduli were also significantly higher for the low-urease activity E. coli compared with the high-urease activity E. coli. The relative resistance to […]