TY - JOUR
T1 - Investigations on gravity influence upon protein crystallization by the gel acupuncture technique
AU - Moreno, Abel
AU - González-Ramírez, Luis Antonio
AU - Hernández-Hernández, María De Los Angeles
AU - Oliver-Salvador, Carmen
AU - Soriano-García, Manuel
AU - Rodríguez-Romero, Adela
N1 - Funding Information:
A.M. and A.R.-R. acknowledge grants from DGAPA projects number IN 218597 and IN 201997, respectively. We thank Prof. Alex McPherson, from the University of California at Irvine, for supplying the STMV solution and giving the crystallization conditions of STMV to perform these investigations. One of the authors (M.C.O.-S.) acknowledges financial support from COFAA-IPN and scholarships from the committee of the ICCBM-7. L.A.G.-R. and M.A.H.-H. acknowledge the lodging scholarship from the committee of the ICCBM-7. We thank the Laboratorio Universitario de Estructura de Proteinas from the Instituto de Quı́mica, UNAM, where all X-ray analyses were performed. Finally, we also acknowledge M.C. Georgina Espinosa, from the Instituto de Quimica, UNAM for all experimental X-ray measurements and helpful X-ray data analyses. This is the contribution 1666 from the Instituto de Quimica, UNAM.
PY - 1999/1/15
Y1 - 1999/1/15
N2 - Most investigations on biological macromolecules are important for the knowledge of the functions in living organisms. Nowadays it is well known that the three-dimensional structure of proteins is obtained either by NMR or X-ray crystallographic methods. The crucial part in the latter is the availability of high-quality crystals in order to perform structural characterization. Nevertheless, there are some approaches to overcome this problem from the statistical [Jancarik and Kim, J. Appl. Crystallogr. 24 (1991) 409] and physico-chemical point of view [Riès-Kautt and Ducruix, Methods in Enzymology 276 Part A, Ch. 3, 1997, p. 23]. Once the crystals are obtained, the following part of the research must be focused on growing the crystal in order to have an appropriate size for X-ray analysis. There are additional advances in the methods for crystallizing, growing and determining what kind of biophysical or biochemical parameters have to be taken into account in order to obtain a high quality protein crystal, these advances have been already published elsewhere [Ducruix and Giegé, Crystallization of Nucleic Acids and Proteins. A Practical Approach, IRL Press, Oxford, 1991; McPherson, The Preparation and Analysis of Protein Crystals, Wiley, New York, 1982]. In order to evaluate these parameters, we have developed a new technique, called the gel acupuncture technique for crystallizing proteins inside an X-ray capillary tube as well as for trying to study the "in situ" crystal growth phenomena [García-Ruiz et al. Mater. Res. Bull. 28 (1993) 541; García-Ruiz and Moreno, Acta Crystallogr. D 50 (1994) 484]. In this work, we present our recent investigations on the influence of the gravity vector upon protein crystallization. Three proteins were chosen in order to test this possible influence, taking into account the size of each: satellite tobacco mosaic virus (1000 kDa) and two proteins of "low molecular weight", thaumatin I (22 kDa) and concanavalin A (200 kda). The experimental set-up was the same for the gel acupuncture technique [García-Ruiz et al. Mater. Res. Bull. 28 (1993) 541] and the experiments were carried out ranging from 0° (parallel) to 180° (anti-parallel) to the gravity vector to check its influence on protein crystallization. Thus, the counter-diffusion phenomena in protein crystallization were evaluated from parallel, 45°, 90° up to anti-parallel transport of the protein molecules to the gravity vector. Finally, we discussed why the molecular weight of the protein system should be taken into account in order to avoid a sedimentation phenomena and how the crystal growth technique is determined in order to keep the same diffusion pattern throughout the experiment.
AB - Most investigations on biological macromolecules are important for the knowledge of the functions in living organisms. Nowadays it is well known that the three-dimensional structure of proteins is obtained either by NMR or X-ray crystallographic methods. The crucial part in the latter is the availability of high-quality crystals in order to perform structural characterization. Nevertheless, there are some approaches to overcome this problem from the statistical [Jancarik and Kim, J. Appl. Crystallogr. 24 (1991) 409] and physico-chemical point of view [Riès-Kautt and Ducruix, Methods in Enzymology 276 Part A, Ch. 3, 1997, p. 23]. Once the crystals are obtained, the following part of the research must be focused on growing the crystal in order to have an appropriate size for X-ray analysis. There are additional advances in the methods for crystallizing, growing and determining what kind of biophysical or biochemical parameters have to be taken into account in order to obtain a high quality protein crystal, these advances have been already published elsewhere [Ducruix and Giegé, Crystallization of Nucleic Acids and Proteins. A Practical Approach, IRL Press, Oxford, 1991; McPherson, The Preparation and Analysis of Protein Crystals, Wiley, New York, 1982]. In order to evaluate these parameters, we have developed a new technique, called the gel acupuncture technique for crystallizing proteins inside an X-ray capillary tube as well as for trying to study the "in situ" crystal growth phenomena [García-Ruiz et al. Mater. Res. Bull. 28 (1993) 541; García-Ruiz and Moreno, Acta Crystallogr. D 50 (1994) 484]. In this work, we present our recent investigations on the influence of the gravity vector upon protein crystallization. Three proteins were chosen in order to test this possible influence, taking into account the size of each: satellite tobacco mosaic virus (1000 kDa) and two proteins of "low molecular weight", thaumatin I (22 kDa) and concanavalin A (200 kda). The experimental set-up was the same for the gel acupuncture technique [García-Ruiz et al. Mater. Res. Bull. 28 (1993) 541] and the experiments were carried out ranging from 0° (parallel) to 180° (anti-parallel) to the gravity vector to check its influence on protein crystallization. Thus, the counter-diffusion phenomena in protein crystallization were evaluated from parallel, 45°, 90° up to anti-parallel transport of the protein molecules to the gravity vector. Finally, we discussed why the molecular weight of the protein system should be taken into account in order to avoid a sedimentation phenomena and how the crystal growth technique is determined in order to keep the same diffusion pattern throughout the experiment.
KW - Crystal growth
KW - Gel acupuncture technique
KW - Microgravity
KW - Protein crystallization
UR - http://www.scopus.com/inward/record.url?scp=0033513805&partnerID=8YFLogxK
U2 - 10.1016/S0022-0248(98)00835-5
DO - 10.1016/S0022-0248(98)00835-5
M3 - Artículo
SN - 0022-0248
VL - 196
SP - 587
EP - 594
JO - Journal of Crystal Growth
JF - Journal of Crystal Growth
IS - 2-4
ER -