{'fraction_non_alphanumeric': 0.012670565302144249, 'fraction_numerical': 0.0, 'mean_word_length': 5.54140127388535, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Antigenic structure of poliovirus.

The molecular basis for future developments of poliovirus vaccines is the detailed knowledge of the structure of the virion. Different types and forms of poliovirus particles are detected in virus preparations. Physical and chemical properties characterize the virion better than its electron microscopic image. The compact poliovirus particle is dissociated only by strong denaturizing agents into four polypeptides and RNA. The best analytical method to separate and characterize these polypeptides is the two-dimensional gel electrophoresis. Isoelectric focusing in urea sucrose gradients gives excellent separations also on a preparative scale. The antigenicity of poliovirus particles is the consequence of a complex cleavage pathway leading from the originally translated polyprotein to virus particles. Bearing in mind the need for a special conformation of the virus protein for N-antigenicity, ways are discussed of how to produce a non-infectious poliovirus vaccine in the future.