Dear all, One of my enzymes crystallized in 0.1 M citric acid pH 3.5 and 25% PEK 3350. The structure solution reveals, citrate molecule is occupying the active site. Moreover citrate mediates the dimer formation. I tried crystallization in the same condition with ligand using soaking with different concentrations of ligands and lower concentration of citric acid (below 0.5 M of citric acid, crystals are broken). Cocrystallization also tried. I collected several data sets with these combinations. The Structure solutions from all these data sets give only citrate complex. I could not get the enzyme-ligand complex
I found crystals only in citrate condition. Any suggestions !! Thanks. Skkannu
