On the Quality of Protein Crystals Grown under Diffusion Mass-transport Controlled Regime (I)
Metadatos
Afficher la notice complèteAuteur
Gavira Gallardo, José Antonio; Otálora, Fermín; González Ramírez, Luis Antonio; Melero, Emilio; Van Driessche, Alexander Edgard Suzanne; García Ruiz, Juan ManuelEditorial
MDPI
Materia
Protein crystallization Microgravity Agarose Counterdiffusion
Date
2020-01-25Referencia bibliográfica
Gavira, J. A., Otálora, F., González-Ramírez, L. A., Melero, E., van Driessche, A. E., & García-Ruíz, J. M. (2020). On the Quality of Protein Crystals Grown under Diffusion Mass-transport Controlled Regime (I). Crystals, 10(2), 68.
Patrocinador
This study was supported by projects ESP2005-23831-E and ESP2007-29071-E (Spanish Ministry of Education and Science) and BIO2016-74875-P (JAG) (MINECO), Spain co-funded by the Fondo Europeo de Desarrollo Regional, FEDER funds, European Union.Résumé
It has been previously shown that the diffraction quality of protein crystals strongly depends
on mass transport during their growth. In fact, several studies support the idea that the higher the
contribution of the diffusion during mass transport, the better the diffraction quality of the crystals. In
this work, we have compared the crystal quality of two model (thaumatin and insulin) and two target
(HBII and HBII-III) proteins grown by two different methods to reduce/eliminate convective mass
transport: crystal growth in agarose gels and crystal growth in solution under microgravity. In both
cases, we used identical counterdiffusion crystallization setups and the same data collection protocols.
Additionally, critical parameters such as reactor geometry, stock batches of proteins and other
chemicals, temperature, and duration of the experiments were carefully monitored. The diffraction
datasets have been analyzed using a principal component analysis (PCA) to determine possible trends
in quality indicators. The relevant indicators show that, for the purpose of structural crystallography,
there are no obvious differences between crystals grown under reduced convective flow in space
and convection-free conditions in agarose gel, indicating that the key factor contributing to crystal
quality is the reduced convection environment and not how this reduced convection is achieved. This
means that the possible detrimental effect on crystal quality due to the incorporation of gel fibers into
the protein crystals is insignificant compared to the positive impact of an optimal convection-free
environment provided by gels. Moreover, our results confirm that the counterdiffusion technique
optimizes protein crystal quality and validates both environments in order to deliver high quality
protein crystals, although other considerations, such as protein/gel interactions, must be considered
when defining the optimal crystallization setup.