posted on 2021-04-07, 14:33authored byYiran Qu, Lijie Wang, Shuang Yin, Bingyang Zhang, Yan Jiao, Yan Sun, Anton Middelberg, Jingxiu Bi
Human
ferritin is regarded as an attractive and promising vaccine
platform because of its uniform structure, good plasticity, and desirable
thermal and chemical stabilities. Besides, it is biocompatible and
presumed safe when used as a vaccine carrier. However, there is a
lack of knowledge of how different antigen insertion sites on the
ferritin nanocage impact the resulting protein stability and performance.
To address this question, we selected Epstein–Barr nuclear
antigen 1 as a model epitope and fused it at the DNA level with different
insertion sites, namely, the N- and C-termini of ferritin, to engineer
proteins E1F1 and F1E1, respectively. Protein properties including
hydrophobicity and thermal, pH, and chemical stability were investigated
both by molecular dynamics (MD) simulation and by experiments. Both
methods demonstrate that the insertion site plays an important role
in protein properties. The C-terminus insertion (F1E1) leads to a
less hydrophobic surface and more tolerance to the external influence
of high temperature, pH, and high concentration of chemical denaturants
compared to N-terminus insertion (E1F1). Simulated protein hydrophobicity
and thermal stability by MD were in high accordance with experimental
results. Thus, MD simulation can be used as a valuable tool to engineer
nanovaccine candidates, cutting down costs by reducing the experimental
effort and accelerating vaccine design.