Recombinant Prevotella sp MA2016 PsmCas13b (type VI-B CRISPR-associated RNA-guided ribonuclease Cas13b), full length. This construct contains an N-terminal His-tag. Psm Cas13b is a CRISPR-Cas effector that belongs to the class 2 subtype VI-B and effectively targets and silences distinct mammalian ssRNA virus.