{'fraction_non_alphanumeric': 0.0423956931359354, 'fraction_numerical': 0.0013458950201884253, 'mean_word_length': 4.697318007662835, 'pattern_counts': {'":': 0, '<': 3, '<?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}}
Effect of the Configuration of Poly(methacrylic acid) on the Complex Formation with Poly-L-lysine

The effect of the configuration of poly(methacrylic acid) (PMA) on the complex formation with poly-L-lysine (PLL) in aqueous media has been studied by circular dichroism (CD) spectroscopy. Four kinds of polymethacrylic acids, i.e., isotactic (iso), syndiotactic (synd), atactic (at), and conventional (conv) PMA’s, were used. The results indicate that the coexisting iso-PMA always induces α-helix formation for PLL, while the other PMA’s do not. Particularly, in the large excess of PMA fraction, PMA’s other than iso-PMA disturb the helix formation of PLL even at pH 11, where PLL by itself takes the α-helical conformation. The amount by which PMA disturbs the helix formation of PLL is in the order of increasing strength: iso <<synd<conv≤at. This order is parallel to the “degree of atacticity” of PMA. These results, together with the induced CD spectrum data measured by using acridine orange as a chromophore, suggest that the structures of the complexes may be classified into two kinds. One is the structure in which the PMA molecule binds to the right-handed α-helix of PLL in such a manner as to form a super helix around the core; the other is the structure in which both component polymers form random aggregates. The ratio of these structures would depend on the configuration and the mixing ratio of PMA and PLL, as well as on the pH of the surrounding aqueous solutions.