1 research outputs found
Strategies for Editing Virulent Staphylococcal Phages Using CRISPR-Cas10
Staphylococci
are prevalent skin-dwelling bacteria that are also
leading causes of antibiotic-resistant infections. Viruses that infect
and lyse these organisms (virulent staphylococcal phages) can be used
as alternatives to conventional antibiotics and represent promising
tools to eliminate or manipulate specific species in the microbiome.
However, since over half their genes have unknown functions, virulent
staphylococcal phages carry inherent risk to cause unknown downstream
side effects. Further, their swift and destructive reproductive cycle
make them intractable by current genetic engineering techniques. CRISPR-Cas10
is an elaborate prokaryotic immune system that employs small RNAs
and a multisubunit protein complex to detect and destroy phages and
other foreign nucleic acids. Some staphylococci naturally possess
CRISPR-Cas10 systems, thus providing an attractive tool already installed
in the host chromosome to harness for phage genome engineering. However,
the efficiency of CRISPR-Cas10 immunity against virulent staphylococcal
phages and corresponding utility as a tool to facilitate their genome
editing has not been explored. Here, we show that the CRISPR-Cas10
system native to <i>Staphylococcus epidermidis</i> exhibits
robust immunity against diverse virulent staphylococcal phages. On
the basis of this activity, a general two-step approach was developed
to edit these phages that relies upon homologous recombination machinery
encoded in the host. Variations of this approach to edit toxic phage
genes and access phages that infect CRISPR-less staphylococci are
also presented. This versatile set of genetic tools enables the systematic
study of phage genes of unknown functions and the design of genetically
defined phage-based antimicrobials that can eliminate or manipulate
specific <i>Staphylococcus</i> species