Figure 4

Seven MK2 crystal forms were identified (Table 5). (a) Form I: MK2(41–364, K343A, K344A, K364A); 2 M (NH₄)₂SO₄, 35 mM Cymal^®-3 (3-cyclohexyl-1-propyl-β-D-maltoside). (b) Form II: MK2(47–366); 2 M (NH₄)₂SO₄, 100 mM HEPES, pH 7.0, 100 mM Li₂SO₄. (c) Form III: MK2(47–366); 2 M (NH₄)₂SO₄, 0.1 M Na citrate, pH 5.0, 4% 1,4-butanediol. (d) Form IV: MK2(47–366, T222E), 2 M sodium malonate, pH 5.5, 0.01 mM Anapoe 80. (e) Form V: MK2(41–364); 1.5 M Na malonate, pH 8.0. (f) Form VI: MK2(41–364); 1.8 M Na malonate, pH 8.0. (g) Form VII: MK2(41–364); 1.75 M (NH₄)₂SO₄, 0.1 M Na citrate, pH 8.0. Crystals grew to a maximal size of ~0.1–0.2 × 0.1–0.2 × 0.2 mm (Forms V-VII); other crystals were ~0.1 × 0.1 × 0.1 mm (Forms III & IV) or smaller. See Table 5 for additional details.