Table 4. Structural modifications in the length of the 4th α-helix induced by HBsAg C-terminus mutations associated with HBsAg<1000 IU/ml.
| Mutations in HBsAg C-terminus | Length of the 4th alpha helixa | |
|---|---|---|
| Residues | N° of residues | |
| Wild Type | L205-Y225 | 21 |
| V190A | L209-Y225 | 17 |
| V190A + F220L | L205-V224 | 20 |
| S204N | L209-Y225 | 17 |
| S204N + F220L | L209-Y225 | 17 |
| S204N + L205P | L209-Y225 | 17 |
| Y206F | F212-Y225 | 14 |
| Y206F + S204T | L209-Y225 | 17 |
| Y206F + S207I | L209-Y225 | 17 |
| Y206F + S210R | L205-V224 | 16 |
| Y206F + V194A | F206-V224 | 19 |
| Y206F + M197T | L206-Y225 | 20 |
| S210N | G202-V224 | 23 |
| S210N + F220L | S204-Y225 | 22 |
aThe 3D-structures of wt and mutated HBsAg were predicted by a homology modeling approach using a reference validated HBsAg structure and elaborated by I-TASSER server.