Abstract
Strong magnetic fields have been used to improve protein crystal quality. To study the effect of strong magnetic field in obtaining first crystals, which is the pre-requisite for determining crystallographic structures, we screened the crystals of 15 proteins using Sparse Matrix Screen (SMS) in a strong and gradient magnetic field. Statistics showed that magnetic field can significantly increase the crystallization success (hits), and the average hits of the trial proteins from different positions in the magnet were improved by 41.3% compared to the control, whereas by 66.1% at “zero-gravity” position (0g/12T). Compared with 1g/0T, the hits of concanavalin A, chymotrypsinogen A, ribonuclease S and ribonuclease A at 0g/12T increased from 16.7%, 41.7%, 25.0% and 8.2%, to 37.5%, 62.5%, 37.5%, and 20.8% respectively. The hits can be further improved to 2.87 times combining magnetic field and temperature compared to the unfavorable temperature outside the magnet. Further investigations suggest that strong magnetic field can modify protein precipitation behaviour leading to the lift of the precipitate curve in phase diagrams, increasing their crystallizability by enlarging the nucleation zone. This novel method will provide a new means for improving the tried and tested protein crystallization, thus facilitating the development of structural biology.
Competing Interest Statement
The authors have declared no competing interest.
