C22 podovirus infectivity is associated with intermediate stiffness.

Area of Science:

• Microbiology
• Nanotechnology
• Biotechnology

Background:

• Bacteriophages show promise as biological control agents (biocontrols) against pathogenic bacteria.
• Limited phage stability hinders their widespread application as biocontrols.
• Understanding storage conditions that maintain phage infectivity is essential.

Purpose of the Study:

• To investigate the impact of environmental factors on the surface properties and infectivity of the C22 phage.
• To determine optimal conditions for long-term storage and application of bacteriophages as biocontrols.

Main Methods:

• Utilized atomic force microscopy (AFM)-based nano-indentation to assess phage mechanical properties.
• Tested C22 phage in buffers with varying pH and ionic strength.
• Evaluated phage infectivity using plaque assays under identical conditions.

Main Results:

• An intermediate range of phage capsid stiffness correlated with high and stable phage titers.
• High infectivity was maintained for up to 182 days under specific storage conditions.
• External factors altering capsid stiffness negatively impacted phage infectivity.

Conclusions:

• The C22 phage requires a metastable state for maximal infectivity.
• Environmental factors influencing capsid stiffness are critical for maintaining phage viability.
• This research provides insights into optimizing bacteriophage storage for biocontrol efficacy.