vB_LspM-01: a novel myovirus displaying pseudolysogeny in Lysinibacillus sphaericus C3-41

Area of Science:

• Microbiology
• Bacteriology
• Virology

Background:

• Lysinibacillus sphaericus is valuable for mosquito biocontrol and toxic metal bioremediation.
• Bacteriophages influence bacterial genetic diversity and adaptation but can cause industrial contamination.
• Understanding phage-host interactions is crucial for both beneficial applications and mitigating risks.

Purpose of the Study:

• To isolate and characterize a novel bacteriophage, vB_LspM-01, infecting Lysinibacillus sphaericus.
• To investigate the host range and lytic activity of the phage and its endolysin.
• To explore the genomic features and population dynamics of the phage-host system.

Main Methods:

• Isolation and characterization of the Myoviridae family phage vB_LspM-01.
• Determination of phage host specificity and endolysin antimicrobial activity.
• Genomic sequencing, phylogenetic analysis, and gene detection in host populations.
• Mitomycin C induction to study lysogeny-lysis dynamics.

Main Results:

• Phage vB_LspM-01 specifically infected L. sphaericus isolates, with its endolysin showing a broader spectrum.
• The phage genome displayed limited similarity to the host, with many unknown ORFs.
• Phage genes were detected at low frequency in wild populations but increased in resistant populations, without stable inheritance.
• Phage genes were primarily found during the logarithmic growth phase, and mitomycin C induced propagation and lysogeny-lysis switching.

Conclusions:

• The bacteriophage vB_LspM-01 is a specificMyoviridae phage of L. sphaericus with potential applications.
• The phage-born endolysin possesses a wider antimicrobial range than the phage itself.
• vB_LspM-01 can exist in a pseudolysogenic state within L. sphaericus populations, influencing bacterial dynamics.