Genetic engineering of untransformable coagulase-negative staphylococcal pathogens

Area of Science:

• Microbiology
• Molecular Biology
• Bacteriology

Background:

• Coagulase-negative staphylococci (CoNS) are significant opportunistic pathogens.
• Limited knowledge exists on CoNS virulence mechanisms due to challenges in genetic manipulation.
• Existing DNA transformation techniques are often ineffective for many CoNS species.

Purpose of the Study:

• To develop an efficient protocol for plasmid DNA transfer into CoNS.
• To overcome the limitations of current genetic transformation methods for CoNS.
• To facilitate research into the virulence mechanisms of CoNS.

Main Methods:

• Utilized bacteriophage Φ187 for plasmid transduction.
• Engineered a unique Staphylococcus aureus strain (PS187 mutant) for efficient phage packaging.
• Employed a restriction-deficient, modification-proficient S. aureus strain with a CoNS-specific phage receptor.

Main Results:

• Successfully achieved efficient plasmid transfer to a wide range of CoNS.
• Demonstrated successful transduction even in CoNS strains refractory to electroporation.
• Protocol enables plasmid transfer within 1-2 days at high bacteriophage Φ187 titers (10^9 PFU/mL).

Conclusions:

• The developed protocol represents a significant technical advancement for CoNS research.
• This method overcomes major hurdles in studying CoNS genetics and virulence.
• Opens new avenues for investigating CoNS-associated infections and developing therapeutic strategies.