Figure 3.

Effect of temperature on the lattice constant of structures formed by DOPE and DOPE/DOPG with different amounts of protein. The diffracting structures were identified according to the spacing of the diffraction peaks (Fig. 1) as H_II or as Q_II with space group either $\text{P}\text{n}\overline{3}\text{m}$ or $\text{I}\text{m}\overline{3}\text{m}$, corresponding to a bicontinuous structure along the diamond (Q_II^D) or primitive (Q_II^P) infinitely periodic minimal surface, respectively. The y axis is split to emphasize the shift in a_o(H_II) with different amounts of SP. Samples contained 10 mM HEPES, pH 7.0, and 2 mM EDTA. (A) DOPE alone. (B) DOPE/DOPG (9:1, mol/mol). The dashed black line indicates the values of a_o(H_II) for DOPE without DOPG or protein.