Crystal Growth and Crystallography

Abstract

Selected topics that may be of interest for both crystalstructure and crystal-growth communities are overviewed. The growth of protein crystals, along with that of some other compounds, is one of the topics, and recent insights into related phenomena are considered as examples of applications of general principles. The relationship between crystal growth shape and structure is reviewed and an attempt to introduce semiquantitative characterization of binding for proteins is made. The concept of kinks for complex structures is brie¯y discussed. Even at suf®ciently low supersaturations, thē uctuation of steps may not be suf®cient to implement the Gibbs±Thomson law if the kink density is low enough. Subsurface ordering of liquids and growth of rough interfaces from melts is discussed. Crystals growing in microgravity from solution should be more perfect if they preferentially trap stress-inducing impurities, thus creating an impurity-depleted zone around themselves. Evidently, such a zone is developed only around the crystals growing in the absence of convection. Under terrestrial conditions, the self-puri®ed depleted zone is destroyed by convection, the crystal traps more impurity and grows stressed. The stress relief causes mosaicity. In systems containing stress-inducing but poorly trapped impurities, the crystals grown in the absence of convection should be worse than those of their terrestrial counterparts.

Viral capsomere structure, surface processes and growth kinetics in the crystallization of macromolecular crystals visualized by in situ atomic force microscopy

“…2a, 3a-c). A similar mechanism was recently observed for the step advancement on growing thaumatin and lysozyme crystals [24][25][26][27][28].…”

Crystallization of the archaeal transcription termination factor NusA: a significant decrease in twinning under microgravity conditions

“…The rate of protein-molecule diffusion can be represented by the diffusion coefficient of the protein molecules D. The rate of protein-molecule uptake into the crystal can be represented by the kinetic coefficient for the trapping of protein molecules into the crystal . Therefore, the protein concentration on the surface of the crystal can be expressed as D/ (Chernov, 1998;Tanaka et al, 2004a). If this D/ value is small enough, then the crystal can grow from relatively low levels of protein, even though the resulting crystal will be small.…”

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

“…Therefore, the low protein concentration area around the growing crystal is maintained, resulting in the formation of a protein concentration depletion zone (protein depletion zone, PDZ). 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.…”