High Proteolytic Resistance of Spider-Derived Inhibitor Cystine Knots

Figure 1

Proteolytic stability of ICK peptides. Four spider-derived ICK peptides and a non-ICK peptide were incubated with representative GI proteases (a) pepsin, (b) trypsin, (c) chymotrypsin, and (d) elastase at physiological conditions for 4 hours. Results are mean ± SEM for 3 experiments. Significantly degraded () compared to other undegraded peptides. All peptides were resistant to pepsin, and only ProTx-I was degraded by trypsin, chymotrypsin, and elastase while other ICKs were not degraded.

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