Fuente: WIPO "tomato" Described in certain example embodiments herein are engineered Anti-CRISPR (Acr) polypeptides having an Acr polypeptide and one or more cell -penetrating peptides (CPPs) operatively coupled to the Acr polypeptide. Also described in several example embodiments herein are methods of producing and purifying Acr polypeptides and delivering engineered Acr polypeptides to a cell or cell population.