{'fraction_non_alphanumeric': 0.025728987993138937, 'fraction_numerical': 0.010291595197255575, 'mean_word_length': 4.665048543689321, '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}}
Co-expression of Clostridium perfringens α and ε Toxins and Their Immunogenicity

The gene CPA and ETX encoding α and e toxins were amplified from the standard strain C60-2 of type D Clostridium perfingens by PCR,and then they were inserted into pet-Duet-1 vecto,respectively for the construction of co-expression plasmid p ETDuet-1-CPA-ETX. The co-expression plasmid was transformed into BL21( DE3) competent cells. α and e toxins proteins were induced by IPTG before analysis by SDS-PAGE. As a result,both of α and e toxins were detected at 43 and 34 KU by western-blot. Mice immunized with the co-expressed α and e toxins proteins produced high titers of neutralizing antibodies in the serum,which protected the mice against the attack of type D C. perfringens culture filtrate. In addition,mice immunized with the produced co-expressed α and e toxins proteins showed significantly higher surviving rate than with e toxins protein alone when infected with culture filtrate of type D C. perfringens. These results indicated that co-expression of α and e toxins proteins could be used as a new method to prepare vaccines against the pathogens of multiple serotypes.