Acr Catalog is a database of the predicted Acr candidates from Gussow et al.

The CRISPR-Cas are adaptive immunity systems that are present in nearly all archaea and about 40% of bacteria. Viruses evolved multiple anti-defense mechanisms including numerous, diverse anti-CRISPR proteins (Acrs). We employed a machine-learning model to predict 2,500 novel candidate Acr families that consist of 16,919 putative Acrs encoded in genomes of bacterial and archaeal viruses as well as prokaryotes, primarily, within putative proviruses. The results of this analysis are included here as a resource.

For more information, contact Ayal Gussow (ayal.gussow@nih.gov) or Eugene Koonin (koonin@ncbi.nlm.nih.gov).


Ayal B. Gussow, Sergey A. Shmakov, Kira S. Makarova, Yuri I. Wolf, Joseph Bondy-Denomy, Eugene V. Koonin. 2020. Vast diversity of anti-CRISPR proteins predicted with a machine-learning approach. bioRxiv doi: 10.1101/2020.01.23.916767