Light-activated porphyrin-based formulations to inactivate bacterial spores

Authors

  • I. Banerjee,

    1. Howard P. Isermann Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, USA
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  • K.K. Mehta,

    1. Howard P. Isermann Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, USA
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  • J.S. Dordick,

    1. Howard P. Isermann Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, USA
    2. Department of Materials Science and Engineering, Rensselaer Polytechnic Institute, Troy, NY, USA
    3. Department of Biology, Rensselaer Polytechnic Institute, Troy, NY, USA
    4. Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY, USA
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  • R.S. Kane

    Corresponding author
    • Howard P. Isermann Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, USA
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Correspondence

Ravi S. Kane, Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, CBIS 4105, 110 8th Street, Troy, NY 12180, USA. E-mail: kaner@rpi.edu

Abstract

Aim

The objective of this study was to develop porphyrin-based formulations to inactivate Bacillus spores. We probed the effect of porphyrins alone and in combination with germinants against both Bacillus cereus and Bacillus anthracis spores in the presence of light.

Methods and Results

We tested the effect of two different porphyrins, amine-modified protoporphyrin IX (PPIX) and meso-tetra (N-methyl-4-pyridyl) porphine tetra tosylate (TMP). Treatment with the porphyrins alone did not significantly influence spore viability. However, when spores were pretreated with a solution containing the germinants, l-alanine and inosine, the spore viability dropped by as much as 4·5 logs in the presence of light. The extent of inactivation depended on the germination conditions and the type of porphyrin used, with TMP being more effective.

Conclusion

Porphyrins can be used effectively in combination with germinants to inactivate Bacillus spores.

Significance and Impact of the Study

The results of this study provide evidence that porphyrins can be used to inactivate Bacillus spores in the presence of germinants and light irradiation. This finding may be general and may be extended to spores of other pathogens.

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