Chambers, James P.Wright, Elena T.Hunter, BarbaraSerwer, Philip2024-06-282024-06-282023-09-27Biophysica 3 (4): 558-568 (2023)https://hdl.handle.net/20.500.12588/6449Phage characterization for research and therapy can involve newly isolated phages propagated in pathogenic bacteria. If so, characterization requires safety-managing the bacteria. In the current study, we adapt a common and inexpensive reagent, PrimeStore (Longhorn Vaccines and Diagnostics, San Antonio, TX, USA), to safety-manage bacteria in 20 min by selectively inactivating the bacteria. No bacterial survivors are observed among &gt;10⁹ bacteria per ml for a representative of both Gram-negative bacteria (<i>Escherichia coli</i>) and Gram-positive bacteria (<i>Bacillus thuringiensis</i>). This procedure causes no detected inactivation of podophage T3, myophage T4 and siphophage 0105phi7-2. Margins of safety for PrimeStore concentration exist for bacterial inactivation and phage non-inactivation. Thus, general applicability is expected. Subsequent dialysis is used to block long-term effects on phages. Nonetheless, comparable tests should be performed for each pathogenic bacterial strain/phage. Electron microscopy of thin sections reveals inactivation-altered bacterial cytoplasm and a non-disintegrated bacterial envelope (ghosts). Ghosting of <i>E. coli</i> includes re-arrangement of the cytoplasm and the release of endotoxin. The activity of the released endotoxin is &gt;99% reduced after subsequent dialysis, which also removes PrimeStore components. Ghosting of <i>B. thuringiensis</i> includes apparent phase separation within <i>the</i> cytoplasm. The primary application envisaged is biophysical and other screening of phages for therapy of infectious disease.2024-06-28