HK97 fold

The HK97 fold forms the capsid shells of the most abundent viruses on the planet belonging to Duplodnaviria realm. They assemble into icoashedral capsids with a T=1, T=3, T=4 or T=16 symmetry .

Origin:

The HK97 fold is also found in prokaryotic encapsulins, which form icosahedral shells with T=1 or T=3 symmetry. These encapsulins form a monophyletic and less diversified cluster compared to viral HK97 capsid proteins, suggesting a possible viral origin for encapsulins .

Topology

The HK97 fold is composed of conserved elements: N-arm, P-domain, E-loop and A-domain. Moreover additional structure appears in some virus like I-domain, D-loop or G-loop.

BACTERIOPHAGE HK97 capsid 1OHG

Viral structural biology Virus structure predictions
Viral protein folds

Viruses

Realm: Duplodnaviria
- Class: Herviviricetes
  - Order: Herpesvirales
- Class: Caudoviricetes
  - >63 prokaroytic viral families
  - exemple: Peduoviridae