SPring-8, the large synchrotron radiation facility

Inquiry number

SOL-0000001097

Beamline

BL41XU (Macromolecular Crystallography I)

Scientific keywords

A. Sample category	biology, medicine
B. Sample category (detail)	biomolecule, crystal, protein
C. Technique	X-ray diffraction
D. Technique (detail)	single crystal
E. Particular condition	low-T (~ liquid N2)
F. Photon energy	X-ray (4-40 keV)
G. Target information	chemical state, chemical bonding, molecular structure, structure analysis, structural change, function and structure, charge density

Industrial keywords

level 1---Application area	Pharmaceuticals
level 2---Target	drug design, process analytical technology (PAT)
level 3---Target (detail)	protein, drug
level 4---Obtainable information	crystal structure, local structure
level 5---Technique	diffraction, X-ray diffraction

Classification

M10.10 single crystal diffraction

Body text

Sarcoplasmic reticulum (SR)is the organella of muscle cell, and stores calcium (Ca)ion in it. When the muscle cell is stimulated by neuron, calcium ion is released from SR, and it becomes the trigger of muscle contraction. The calcium ATPase is a membrane protein existing within the SR membrane. It transports calcium ion into SR after muscle contraction.

In this case, three-dimensional structure of Ca-ATPase from rat SR was determined by X-ray diffraction experiment at BL41XU (Fig, 1).

Generally, most crystals of membrane protein have only weak ability to diffract X-ray. This enzyme is a large protein with about 110,000 in molecular weight, and the unit cell of its crystal is also large, 166.0ｘ64.4ｘ147.1 Å . In addition, the thickness of its crystal is only less than 20 µm. High brilliant X-ray from undulator of BL41XU was indispensable to collect the good X-ray diffraction data.

Ca-ATPase is paid attention from the viewpoint of cancer treatment and myocardial infarction. Therefore, this result makes those researches advanced greatly.

Figure 1. Structure model of Ca-ATPase

[ C. Toyoshima, M. Nakasako, H. Nomura and H. Ogawa, Nature 405, 647-655 (2000), Fig. 2,
©2000 Nature Publishing Group ]

Source of the figure

Original paper/Journal article

Journal title

C. Toyoshima, et al., Nature 405, 647-655 (2000)

Figure No.

2

Technique

Source of the figure

No figure

Required time for experimental setup

0 hour(s)

Instruments

Instrument	Purpose	Performance
Protein Crystal Diffractometer	To record diffraction data

References

Document name
C. Toyoshima, et al., Nature 405, 647-655 (2000)

Related experimental techniques

Questionnaire

The measurement was possible only in SPring-8. Impossible or very difficult in other facilities.
This solution is an application of a main instrument of the beamline.

Ease of measurement

Middle

Ease of analysis

Middle

How many shifts were needed for taking whole data in the figure?

Four-nine shifts