And proteins have two major parts; the sequence of amino acids that they’re composed of, and how they’re folded. This folding detail is no small thing, as proteins don’t do the right thing when they’re folded wrong.
The BioNtech-Vaccine accounts for this afaik, to prevent the spike-proteins from clumping.
So, even further from regex. The RNA gets turned into a sequence of amino acids, which folds in an extremely complex 3D shape, which bind together with two other proteins to form a large structure, the full shape of which is matched by antibodies.
1. https://www.nytimes.com/interactive/2020/health/pfizer-biont...