Clostridioides difficile CRISPR-cas9 system

We developed a CRISPR-cas9 mutagenesis system for use in C. difficile. As a test of the system, we generated a deletion in the pyrE gene of C. difficile R02091. We sequenced to pyrE deletion isolates (to determine if there were off-target effects of the CRISPR system), an FOA-resistant R20291 isolate and our parent R20291 strain for comparison.