JPH06183400A - Protein crystal growing device - Google Patents

Abstract

PURPOSE:To reduce the quantity of a protein solution, enable the fixing of a precipitated protein crystal, and enable the use of a protein solution container as a capillary for X-ray analysis only by taking out this container by adopting a uniform thin glass capillary tube as the protein solution container of a protein crystal growing device. CONSTITUTION:In a device for bringing a protein solution into contact with a precipitator solution so as to grow a protein crystal by the diffusion of a precipitator at the interface, a protein solution container 1 is formed of plural uniform thin glass capillary tubes, and diffused precipitator molecules are led into the container 1 by the diffusion and the capillary force of the protein solution container 1 to precipitate the protein crystal. After the formation of the crystal, the structure analysis of the protein crystal by X-ray radiation can be performed immediately by taking the container 1 out of a container holding part 4. A small quantity of the protein solution suffices, and the precipitated protein crystal can be fixed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protein crystal growth apparatus, and more particularly to the apparatus that can be used in a weightless space.

[0002]

2. Description of the Related Art A conventional protein crystal growth apparatus will be described with reference to FIG. In FIG. 3, 01 is a protein solution container, 02 is a precipitant solution container, and 03 is a valve. Both the protein solution container 01 and the precipitant solution container 02 have an inner diameter of about 10 mm, and by rotating the central valve 03 counterclockwise by 90 °, the precipitant solution in the left precipitant solution container 02 and the right protein can be This is a system in which the protein solution in the solution container 01 contacts and the protein crystals grow. In FIG. 3, B indicates the contact interface between the protein solution and the precipitant solution.

[0003]

The conventional protein crystal growth apparatus utilizes diffusion at the liquid-liquid interface between the precipitant solution on the left side and the protein solution on the right side shown in FIG. Since the volume of the container is large, it is necessary to prepare a large amount of protein samples, and it is difficult to fix the crystals that are formed. In addition, for structural analysis by X-ray irradiation, an X-ray diffraction capillary (inner diameter of uniform thin glass) There is a problem in that it needs to be transferred to a capillary tube of about 1 mm).

Of these, if the fixation of crystals is insufficient,
Crystals move through the protein solution, increasing the likelihood of contacting each other. The contact of crystals results in the loss of single crystallinity and, in extreme cases, damage to crystals once grown, but these bad results are especially caused when the protein crystals grown in weightless space are collected on the ground. Will be a problem. Further, the work of transferring to a capillary also has a problem that strain is applied to the crystal to impair the single crystallinity, or the crystal is damaged. In view of the above-mentioned state of the art, the present invention aims to provide a protein crystal growth apparatus that does not have the above-mentioned problems that the conventional protein crystal growth apparatus has.

[0005]

The present invention relates to a device for contacting a protein solution with a precipitant solution and growing a protein crystal by diffusing the precipitant at the interface, wherein the protein solution is provided with a plurality of uniformly thin glass capillaries. It is a protein crystal growth apparatus characterized by comprising the following.

[0006]

[Function] By adopting a uniform thin-walled glass capillary tube having an inner diameter of about 1 mm as a protein solution container of a protein crystal growth apparatus, there is no possibility that the crystal will move a large distance after the crystal is formed, and only the container is taken out. so,
The structure analysis by X-ray irradiation can be performed as it is. Also,
Since the protein solution container is made of a plurality of uniform thin glass capillaries having an inner diameter of about 1 mm, the required amount of the solution of the protein solution is small, and it can be used for a valuable protein sample. Furthermore,
Diffusion at the liquid-liquid interface, which is the principle of this type of device, is performed not by a small cross-sectional area of a uniform thin glass capillary tube but by a wide cross-sectional area in the bulb, so that the diffusion interface area does not decrease. Since the cross-sectional area of the part where the crystal growth actually occurs is much reduced, the thermal convection is suppressed inside, a good quality crystal grows under the diffusion-controlled condition, and the response to the temperature control is good. A salt solution, a water-soluble polymer solution, and a water-soluble organic solvent solution are generally used as the precipitant solution used in the present invention.

[0007]

EXAMPLE An example of the protein crystal growth apparatus of the present invention will be described below with reference to FIGS. 1 is a vertical sectional side view thereof, and FIG. 2 is a partially enlarged view of FIG. In FIGS. 1 and 2, 1 is a protein solution container, 2 is a precipitant solution container, 3 is a valve, and 4 is a container holder.

The precipitant molecules of the precipitant solution diffused by the apparatus of the present invention are introduced into the protein solution container 1 by diffusion and the capillary force of the protein solution container 1, and the container 1
Protein crystals are precipitated in the. Thus, according to the apparatus of the present invention, by taking out the protein solution container 1, it is possible to immediately perform the structural analysis of the protein crystal by X-ray irradiation.

Further, in the apparatus of the embodiment of the present invention, when the valve 3 is installed as shown in FIG. 1, since the protein solution is filled in the valve 3, the valve 3 is set to 90 °.
When rotated by °, the precipitant solution and the protein solution come into contact with each other at A in the valve 3 to form an interface. On the other hand, at the position of the valve 03 in the conventional apparatus shown in FIG. 3, the contact interface between both solutions is at the position B of the valve 03 in FIG. 3 due to the rotation of the valve 03. Of course, also in the apparatus of the embodiment of the present invention, if the direction of the valve 3 is reversed by 180 °, the valve 3 is filled with the depositing agent solution, and the contact interface becomes B as in FIG.
It is possible to deal with the situation where a large amount of protein samples are rarely prepared.

[0010]

EFFECTS OF THE INVENTION According to the present invention, a small amount of protein solution is sufficient, and the protein solution container is a capillary tube, so that the precipitated protein crystals can be fixed. Further, since the protein solution container is a uniform thin glass capillary tube, it is possible to use the protein solution container as it is as an X-ray diffraction capillary simply by taking it out from the holding portion.

[Brief description of drawings]

FIG. 1 is a vertical side view of a protein crystal growth apparatus according to an embodiment of the present invention.

FIG. 2 is a partially enlarged view of FIG.

FIG. 3 is a vertical sectional side view of one embodiment of a conventional protein crystal growth apparatus.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Maki Kato 1-1-1, Wadasaki-cho, Hyogo-ku, Kobe-shi, Hyogo Mitsubishi Heavy Industries, Ltd. Kobe Shipyard (72) Inventor Haruyama Miyama, Hyogo-ku, Kobe-shi, Hyogo 1-1-1 Tasakicho Mitsubishi Heavy Industries Ltd. Kobe Shipyard

Claims (1)

[Claims] 1. A device for growing a protein crystal by contacting a protein solution with a precipitant solution and diffusing the precipitant at the interface, wherein the protein solution container comprises a plurality of uniformly thin glass capillaries. A protein crystal growth apparatus characterized by: