Evolution of the CRISPR-Cas9 defence system in <i>Mycoplasma gallisepticum</i> following colonization of a novel bird host.

ABSTRACT: Clustered regularly interspaced short palindromic repeat (CRISPR)-Cas systems are bacterial defences that target bacteriophages and mobile genetic elements. How these defences evolve in novel host environments remains largely unknown. We studied the evolution of the CRISPR-Cas system in Mycoplasma gallisepticum (also named Mycoplasmoides gallisepticum), a bacterial pathogen of poultry that jumped into a passerine host ~30 years ago. Over the decade following the host shift, all isolates displaying a functional CRISPR-Cas system were found not only to harbour completely new sets of spacers, but the DNA protospacer adjacent motif recognized by the main effector M. gallisepticum Cas9 (MgCas9) was also different. These changes in CRISPR-Cas diversity and specificity are co

SUBMITTER: Ipoutcha T 

PROVIDER: S-EPMC11893278 | biostudies-literature | 2024 Nov

REPOSITORIES: biostudies-literature