Fig. 5. The effect of H. aspersa glue proteins on polymers with different degrees of charge. The storage moduli were measured with a dynamic rheometer. Gels contained 1 mg ml^–1 glue proteins (dark bars) or 1 mg ml^–1 BSA as a control (light bars). Agarose (0.2%, N=5), apple pectin (2%, N=7) and methylcellulose (2%, N=6) are neutral or less charged than agar (0.6%, N=7), citrus pectin (2%, N=7) and carboxymethylcellulose (2%, N=7). Values are means ± S.E.M. Asterisks indicate a significant difference (t-test or Wilcoxon two-sample test, P<0.05).