Bio-inspired artificial shells protect living bacterial cells via biomimetic mineralization

Abstract:

[Objective] Bio-inspired artificial mineral shells are used to protect living bacterial cells. [Methods] Bacterial cells were encapsulated in firm and intact mineral shells, where the limited physical space and substance exchange induced the dormancy of living bacteria to decrease the viability loss during long-term preservation and even in extreme environments. Moreover, acids can erode the shells to reactivate the bacteria. [Results] Compared with the un-mineralization treatment (EcN), the mineralization treatment (EcN@CaCO₃) increased the bacterial viability by a maximum of 262 folds in a 32-day storage experiment and the survival rate by 837, 171, 59.1, and 729.7 folds at pH 2.5, pH 12.0, 80 ℃, and in the presence of an antibiotic, respectively. [Conclusion] We employed biomimetic mineralization to improve the stability of bacterial cells in storage, which can provide a research basis for the application of microorganisms in environmental engineering, food production, and biomedical engineering.