Elucidating Bacterial Spore Dynamics through Lanthanide-Enhanced Live Imaging

Area of Science:

• Microbiology
• Biotechnology
• Analytical Chemistry

Background:

• Distinguishing between dormant and active bacterial spores is crucial for public health and safety.
• Existing methods, like the Schaeffer-Fulton method, are often destructive, time-consuming, and labor-intensive.
• There is a need for rapid, non-destructive techniques for bacterial spore analysis.

Purpose of the Study:

• To develop a simple, quick, and non-destructive method for differentiating dormant and germinated bacterial spores.
• To utilize lanthanide-beta-diketonate complexes for direct single-spore visualization.

Main Methods:

• Employing lanthanide-beta-diketonate complexes for instantaneous staining of bacterial spores.
• Observing differential staining patterns between dormant (nonfluorescent core) and germinated (fluorescent core) spores.
• Utilizing a USB microscope for low-cost imaging of spores in various matrices, including milk.

Main Results:

• The lanthanide complexes successfully stained dormant and germinated spores from five bacterial species, including *Bacillus*, *Clostridium*, and *Clostridioides*.
• Dormant spores showed a nonfluorescent core, while germinated spores exhibited a brightly fluorescent core.
• The method is rapid, requires minimal sample processing, and allows for live imaging due to low complex toxicity.

Conclusions:

• Lanthanide-beta-diketonate complexes provide an effective, non-destructive method for distinguishing bacterial spore states.
• This technique offers a valuable, low-cost tool for studying bacterial spores in diverse settings, enhancing biosecurity and food safety.
• The versatility in complex formulation allows for tailored spore visualization.