Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Bay Area To Get Unique X-Ray Microscopy Resource

01.04.2004


This x-ray tomography image of a yeast cell taken at the ALS with XM-1 is an example of what could be done with the proposed XM-2. Internal organelles are color-coded according to x-ray absorption. Shown in red are the nucleus (smaller sphere) and large vacuole. Lipid droplets are shown in white, and cytoplasmic structures are shown in either orange or green.


Carolyn Larabell and Mark Le Gros used the current transmission x-ray microscope at the ALS, XM-1, to demonstrate the potential of their new microscopy resource


A first-of-its-kind x-ray microscope being built for the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory (Berkeley Lab) holds forth the promise of “cat scans” for biological cells, and other unprecedented capabilities for cell and molecular biology studies. The new microscopy resource also promises a better understanding of human diseases at the molecular level and possibly new discoveries for treating those diseases. Now, researchers with Berkeley Lab and the University of California at San Francisco (UCSF), have received grants from the National Institutes of Health (NIH) and the U.S. Department of Energy (DOE) to build and operate this microscope.

“X-ray microscopy is an emerging new technology that will expand the existing imaging toolbox for cell and molecular biologists, and we would like to make this technology available to the greater biological community,” says cell biologist and microscopy expert Carolyn Larabell, who holds a joint appointment with UCSF’s Anatomy Department, and with Berkeley Lab’s Physical Biosciences Division. She is the principal investigator for this project. Berkeley Lab physicist Mark Le Gros is the co-principal investigator.

“Although there are currently many powerful techniques for imaging biological cells, each with its own unique strengths and limitations, there remains a gap between the information that can be obtained with light microscopy and electron microscopy,” Larabell says. “X-ray microscopy can bridge this gap by combining some of the best features associated with light and electron microscopy, plus bringing in some entirely new capabilities.”



To build this new microscope, Larabell and Le Gros have been awarded $2.5 million from NIH and DOE. The money will be dispersed to UCSF through NIH’s National Center for Research Resources (NCRR). Under the terms of this grant, Larabell and Le Gros will establish a Biomedical Technology Resource Center at the ALS, which means the instrument will be available to biomedical researchers throughout the nation. The new ALS x-ray microscopy resource will be the first of its kind and the 43rd such center sponsored by NCRR. Together, NIH and DOE will contribute about $1.3 million to run the microscope for each of its first five years of operation. The grants can then be renewed for additional five-year periods.

What Larabell and Le Gros have proposed is a transmission x-ray microscope (TXM) off a bend magnet beamline at the ALS, an electron-based synchrotron/storage ring capable of generating x-ray beams that are one hundred million times brighter than those from the best x-ray tubes. With beams of this intensity, the new TXM will be able to image whole, hydrated cells at resolutions of about 35 nanometers, and specific structural elements within the cell at a resolution of at least 25 nanometers. Future improvements could put the resolution of this microscope as fine as 10 nanometers, which is about the size of a protein.

Imaging data will be collected at breathtaking speed compared with the time-consuming procedures required to collect data via electron microscopy. Obtaining a complete data set for an x-ray tomography image should require less than three minutes, compared to the days and even weeks required for electron microscopy.

“We’ll be able to collect data faster than we can process it,” Larabell says. “We’ll be able to examine whole cells, identify subcellular components and locate macromolecules inside cells at substantially better resolutions than light microscopy and without the elaborate specimen preparations needed for electron microscopy.”

Microscopy using photons that fall within the visible light region of the electromagnetic spectrum remains the workhorse of biology because it enables scientists to examine living cells in their natural state. Resolution, however, is typically no better than 200 nanometers, and that is only when the light is focused on a single spot.

Microscopy techniques based on the use of electrons can provide images at a resolution of five nanometers or better. However, samples must be sliced thin and put through an elaborate chemical preparation and stained in order for the electrons to penetrate and yield high-res images.

With transmission x-ray microscopy, samples are rapidly frozen and need no further chemical alteration or staining to be imaged. Furthermore, 3-D subcelluar structures within 10 nanometers of one another can be captured in the same image, which means interactions between two or more proteins can be observed. Because of the quick turnaround time between sample preparation and data collection, scientists using the new TXM at the ALS will be able to accumulate a statistically significant volume of data within a relatively short time.

Larabell and Le Gros have been using an existing TXM at the ALS to demonstrate the potential of using this technology in cell and molecular biology studies. The existing TXM, called XM-1, the only one of its kind in the United States, was designed and is operated by the Center for X-ray Optics primarily for the study of materials. The new TXM, dubbed XM-2, will be optimized for biology and will therefore have several advantages, including improved zone plates, the optic devices composed of nanometer-scale concentric metal rings that are used to focus x-rays for imaging purposes.

“Whereas XM-1 could only be used to study suspension cell lines, XM-2 can be used to study adherent cell lines as well,” says Larabell. “In addition, we’ll have greater energy tunability with XM-2 which means it can be used to do imaging of thicker samples as well as high-res images of thinner samples just by spinning to a different zone plate.”

XM-2’s ability to use a multiple choice of x-ray beam energies will also open the door to multiple labeling of proteins. This means scientists will be able to use the microscope to study protein complexes as well as individual proteins. XM-2 should also prove to be a powerful tool for utilizing tomographic imaging techniques in x-ray microscopy. In a study using XM-1, Larabell and Le Gros performed CT scans of whole, rapidly frozen yeast cells and obtained 3-D reconstructions at a resolution of better than 50 nanometers.

“No contrast enhancement reagents were used, the cells were not embedded or sectioned, and collection of the entire data set took less than an hour,” says Larabell. “While our resolution was not quite as good as that from cryo-electron tomography, it was more than sufficient for many of the scientific questions being asked. Also, we’ve not yet reached the limit of resolution that’s theoretically possible with x-ray tomography.”

Under the terms of the NIH-NCRR grant, XM-2 is expected to be up and running at the ALS in 2006.

Berkeley Lab is a U.S. Department of Energy national laboratory located in Berkeley, California. It conducts unclassified scientific research and is managed by the University of California.

Lynn Yarris | LBNL
Further information:
http://www.lbl.gov/Science-Articles/Archive/ALS-x-ray-microscopy.html
http://www.lbl.gov/wonder/larabell.html

More articles from Life Sciences:

nachricht How brains surrender to sleep
23.06.2017 | IMP - Forschungsinstitut für Molekulare Pathologie GmbH

nachricht A new technique isolates neuronal activity during memory consolidation
22.06.2017 | Spanish National Research Council (CSIC)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>