Peptide co-assembly is attractive for creating biomaterials with new forms and functions. Emergence of these properties depends on the peptide content of the final assembled structure, which is difficult to predict in multicomponent systems. Here using experiments and simulations we show that charge governs content by affecting propensity for self- and co-association in binary CATCH(+/−) peptide systems. Equimolar mixtures of CATCH(2+/2−), CATCH(4+/4−), and CATCH(6+/6−) formed two-component β-sheets. Solid-state NMR suggested the cationic peptide predominated in the final assemblies. The cationic-to-anionic peptide ratio decreased with increasing charge. CATCH(2+) formed β-sheets when alone, whereas the other peptides remained unassembled. Fibrillization rate increased with peptide charge. The zwitterionic CATCH parent peptide, “Q11”, assembled slowly and only at decreased simulation temperature. These results demonstrate that increasing charge draws complementary peptides together faster, favoring co-assembly, while like-charged molecules repel. We foresee these insights enabling development of co-assembled peptide biomaterials with defined content and predictable properties.

肽共组装对于创造具有新形式和功能的生物材料具有吸引力。这些特性的出现取决于最终组装结构的肽含量，这在多组分系统中很难预测。在这里，通过实验和模拟，我们表明电荷通过影响二元 CATCH(+/-) 肽系统中自缔合和共缔合的倾向来控制内容。CATCH(2+/2−)、CATCH(4+/4−) 和 CATCH(6+/6−) 的等摩尔混合物形成双组分 β-折叠。固态核磁共振表明阳离子肽在最终组装中占主导地位。阳离子与阴离子肽的比率随着电荷的增加而降低。CATCH(2+) 单独时形成 β-折叠，而其他肽保持未组装状态。纤维化率随着肽电荷的增加而增加。两性离子 CATCH 母肽“Q11”仅在降低的模拟温度下缓慢组装。这些结果表明，增加电荷可以更快地将互补肽吸引到一起，有利于共组装，而带相同电荷的分子则相互排斥。我们预见这些见解将有助于开发具有确定含量和可预测特性的共组装肽生物材料。