Bacterial virus anti-defence systems · sequence & structure resource

Encyclopaedia of Bacterial Virus Anti-Defence Systems


Protein: AcrIIA26

Download all data for this protein (.zip)

Overview

Mode of Action (MoA) AlphaFold 3 predicts a high confidence interaction between Cas9 (https://www.ncbi.nlm.nih.gov/protein/QHB64844.1) and AcrIIA26 (ipTM = 0.87, pTM = 0.79)
Evidence Expression of AcrIIA26 in E. coli prevented Cas9-mediated plasmid interference, particularly with SpyCas9 (ECO_0000017). AcrIIA26 was cloned and tested in interference assays, which showed full protection. In vitro cleavage reactions showed that AcrIIA26 blocked RNP–DNA binding. EMSAs confirmed prevention of RNP-DNA complex formation (ECO_0001807). In human cells, co-transfection of AcrIIA26 with SpyCas9 led to near-complete loss of indel formation, supporting a DNA-binding inhibition mechanism. Binding it supported by computational structure modeling evidence (ECO_0006368).
MoA Category binds and inhibits host defence system (putative)
Subtype(s) of the defence system(s) inhibited by the protein Defence Subtype Streptococcus thermophilus and Streptococcus pyogenes type II-A CRISPR-Cas
Relevant publication(s) DOI 10.1093/nar/gkac099
Other components of the anti-defence system Multicomponent System -
Known structure in PDB PDB ID -
Genome(s) encoding the protein Protein Source MGE in Streptococcus sp.
Defence system(s) inhibited by the protein Defences CRISPR-Cas

3D structure

AlphaFold 3 model.

Download structure file

Feature viewer - predicted secondary structure

Download features JSON file

Pfam annotations

No Pfam domains found

Sequence Viewer

Amino acid position: -

MKKLYIQTNQFANGELQVENTSYELCDTFKELYSVASNLVDENTLNFVEDNFIEQNYKDEYNGVYENDGDTGEFVGQVFENKVTEEQFKELLEQLEITYTEFDPEEELAKCIANKNRKSEFYGNGLKVIAEYLESISHEDALAVVTYYYFYFGFGYEDQLISDIKDDQEDGVKFEHVERSETI