Distribution coefficients of protein impurities in ferritin and lysozyme crystals Self-purification in microgravity

Impurity effect on defect formation of protein crystals

“…These impurities could be incorporated into protein crystals to form lattice defects. In the last decades, therefore, numerous studies about impurity effects on protein crystal growth have been carried out [2][3][4][5][6]. Vekilov et al [7] reported the impurity effect on the growth step kinetics.…”

Influence of gravity on post-nucleation transport in liquid/liquid diffusion chamber of protein crystallization

“…There are also evidences showing that the enhanced convective supply of impurities to the C/S interface could cause the crystal defects [6]. As experiments revealed, the crystals grown in terrestrial condition incorporated higher amount of impurities than those grown in space [7]. On the contrary, the solutions would remain static in 0g case, and the depletion zone would be much thicker than in 1g case.…”

“…On the contrary, the solutions would remain static in 0g case, and the depletion zone would be much thicker than in 1g case. The static diffusion field and the thicker depletion zone have a purifying effect by decreasing the opportunity of impurities to access the protein crystal [7,8]. Meanwhile, the thicker depletion zone in 0g case may eliminate the occurrence of new nucleus near the growing crystals.…”

“…To date, the accumulation of the space experiments and ground-based studies give us better understanding of the effects of gravity on protein crystal growth. The gravity-induced solutal convection influences the protein crystal growth mainly through modifying the bulk transport of solutes and the interface kinetics [3][4][5][6][7]. The convection promotes the transport of solutes and the impurities, and increases the solute supersaturation and the impurity concentration at the crystal/solution (C/S) interface, but decreases the thickness of the depletion zone.…”

Numerical model of protein crystal growth in a diffusive field such as the microgravity environment

“…The PDZ helps grow the crystal at a low supersaturation (Chernov, 1998;Otá lora et al, 2001), eventually suppressing the disorder of protein molecules in the crystal. Following similar steps as the protein molecules, a low-impurity concentration area around the growing crystal (impurity depletion zone, IDZ) is formed (Chernov, 1998; Thomas et al, 2000), also suppressing crystal disorder.…”