1. BACTERIORHODOPSIN: PUMPING IONS
By Lori Tamura
(Contact: hudel@anx12.bio.uci.edu)

A live cell cannot be a closed system; information and material, often in the form of ions, must be able to pass through cell membranes. Bacteriorhodopsin (BR) is a membrane-embedded protein that can actively "pump" ions from one side of the membrane to the other, against an electrochemical gradient. The energy for this process comes from a photon of visible light, which sets into motion a series of structural changes within the BR molecule that favor active ion transport. Researchers from the University of California, Irvine, have obtained atomic-resolution structures of BR crystals in two different states: one at the beginning of the ion-transport cycle and another in midstroke. Analysis of the small, but significant, structural differences between the two states provides insight into the mechanisms and forces that push and pull ions through the membrane, against the electrochemical tide.

Read the full story at http://www-als.lbl.gov/als/science/sci_archive/rhodopsin.html.

Publications about this research: H. Luecke, B. Schobert, H.-T. Richter, J.-P. Cartailler, and J. K. Lanyi, "Structural Changes in Bacteriorhodopsin During Ion Transport at 2 Angstrom Resolution," Science 286, 255 (1999); H. Luecke, B. Schobert, H.-T. Richter, J.-P. Cartailler, and J. K. Lanyi, "Structure of Bacteriorhodopsin at 1.55 Angstrom Resolution," J. Mol. Biol. 291, 899 (1999).

2. PETROFF REPORT GIVES HIGH MARKS TO THE ALS

The quality of the science being done at the ALS is excellent to outstanding, according to a subpanel commissioned to review the ALS by the Basic Energy Sciences Advisory Committee (BESAC) of the U.S. Department of Energy (DOE). A full report on the review was presented to BESAC on February 29 by the subpanel's chair, Yves Petroff, Director General of the European Synchrotron Radiation Facility. The subpanel was charged in general with reexamining the issues raised in the Birgeneau report (from a previous BESAC review). In particular, the goals of this review were to evaluate the quality of the ALS's science programs, verify appropriate management response to Birgeneau criticisms, gauge user satisfaction, and explore the ALS's vision for the future.

In support of its judgment of the excellence of ALS scientific programs, the report recapitulated the many science highlights that were presented to the subpanel by ALS users during the review last month (see the agenda at http://www-als.lbl.gov/als/als_news/besac.html). The report also compared the number of high-profile ALS publications in structural biology, solid-state physics, and chemistry with that from other U.S. facilities, noting that ALS scientific "productivity" is remarkable in solid state physics and chemistry and is especially impressive in structural biology. The report also questioned the validity of the Birgeneau report's observation that "important scientific issues which require UV radiation have decreased in number compared to those which require hard x-rays." It was pointed out that, while hard x rays are needed to probe a material's structural properties, UV light and soft x rays are required to probe electronic properties; research into high-Tc superconductors was cited as one example where results obtained using UV light are much more fundamental than those obtained using x rays.

The report also noted that Berkeley Lab management reacted very quickly and effectively to the criticisms of the Birgeneau report. The appointment of Daniel Chemla as Director, the elevation of the ALS to Divisional status, the increased links with the University of California, Berkeley, the organizational changes, and the improved interaction with users and the Scientific Advisory Committee have dramatically affected the ALS's scientific output.

The subpanel strongly supported the following future directions for the ALS as laid out by Director Chemla: molecular environmental science (in particular the chemistry associated with toxic and radioactive contamination), photoemission electron microscope (PEEM3) magnetic and polymer nanostructure research (noting strong competition in Europe), and femtosecond spectroscopy and diffraction (emphasizing the ALS's unique position with respect to capabilities and talent in this area). In addition, the subpanel endorsed the vigorous structural biology program (eight new crystallography beamlines with varying research and technological demands) being funded with non-DOE money. For more about the subpanel's conclusions and recommendations with respect to ALS science and user relations, see UEC Corner, below.

3. MACROMOLECULAR CRYSTALLOGRAPHY BEAMTIME PROPOSALS DUE TODAY

Today is the last day for independent investigators to submit proposals to the User Services Office for conducting research at the Macromolecular Crystallography Facility (Beamline 5.0.2). This is the third and final notice for the July-December 2000 proposal cycle. (The deadline for the subsequent cycle is September 1, 2000.) Scientists wishing to renew a previous proposal must notify the ALS User Services Office Manager, Bernie Dixon, at alsproposals@lbl.gov.

The following resources are available for further information:

ALS User Services Administrator

alsuser@lbl.gov

Independent-investigator process/proposal form (PDF)

http://www-als.lbl.gov/als/quickguide/independinvest.html

Beamline 5.0.2 information

http://www-als.lbl.gov/als/als_users_bl/5.0-Datasheet.pdf

http://www-als.lbl.gov/als/quickguide/bl5.0.2.html

Macromolecular Crystallography Facility Web site

http://www.lbl.gov/LBL-Programs/mcf/

4. ICESS8 CONFERENCE WEB SITE UPDATED
(Contact: icess@electron.lbl.gov)

Complete information is now available on the Web for the Eighth International Conference on Electronic Spectroscopy and Structure (ICESS8), to be held at the Clark Kerr Campus of the Univ. of California, Berkeley, on August 8-12, 2000. The site, at http://www-als.lbl.gov/icess, includes full information on the scientific program, invited speakers, registration, housing, abstract submittal, proceedings papers, and travel. Attendees are strongly encouraged to take advantage of the convenient on-line registration and abstract submittal functions now available through this site.

5. EQUIPMENT INSPECTIONS NECESSARY FOR ELECTRICAL SAFETY
(Contact: GMPerdue@lbl.gov)

Maintaining a safe work environment for ALS users is a complicated task. Due to the very nature of research at the ALS, new equipment is constantly being installed and existing equipment is frequently reconfigured. In addition, much of the equipment is made by ALS users and may or may not meet electrical standards acceptable to Berkeley Lab.

The ALS recognizes that, because of these factors, electrical hazards are one of our greatest vulnerabilities, and the cost of accidents is high. With the growing number of users on the experiment floor, the need for inspections is also increasing. The intent of these inspections is to help users remain safe while they perform experiments. Although every effort is made to respect users' schedules, delays may occur while unsafe conditions are corrected. ALS management asks users for their understanding during any such delays and welcomes their suggestions as to how they may be better served. Please do not hesitate to contact Georgeanna Perdue (ext. 7407, GMPerdue@lbl.gov) with any questions or comments.

6. UEC CORNER: NOTES FROM THE USERS' EXECUTIVE COMMITTEE
by Nora Berrah
(Contact: berrah@wmich.edu)

The DOE advisory panel led by Dr. Yves Petroff gave the ALS a glowing review at the last BESAC meeting in Washington on February 28-29, 2000. According to the report, the members of the review panel were impressed by the ALS's scientific quality and productivity. In his recommendations, Dr. Petroff said, "It is clear that the ALS is doing an outstanding job in many areas. None of the criticisms of the Birgeneau report are still valid."

Dr. Petroff and his team identified the following areas of excellence: (1) structural biology; (2) femtosecond and picosecond dynamics in condensed matter and in the gas phase; (3) electronic processes and many-body effects in highly correlated systems, magnetic nanostructures, and correlation in small systems; (4) surface science, thin films, and microscopy; (5) ultra high-resolution spectroscopy of gas-phase atoms, ions, and molecules; (6) chemistry and catalysis (wet, heterogeneous, nanoscale chemistry and biochemistry, radical dynamics, catalytic interfaces at atmospheric pressure); and (7) analytical sciences and metrology. These were listed in the conclusions given to BESAC.

Dr. Petroff addressed the issue of user relations and pointed out that ALS management and the user community have established productive, respectful, and direct two-way communication. In the presentation, Dr. Petroff also supported users' recommendations for (1) an increase in the size of the Scientific Support Group, (2) funds for postdoctoral associates, and (3) support for constructing a users' building adjacent to the ALS.

Dr. Petroff recommended at the end of his talk that any penalties imposed on the ALS in light of the Birgeneau report be lifted. We are all very happy to be at the end of a difficult era and to learn that, according to a recent Science article written by David Malakoff (Vol. 287, p. 1733), Dr. Pat Dehmer, Director of the DOE Office of Basic Energy Sciences, said, "any lingering prejudice against the ALS should be washed away."

I would like to remind you that the UEC will meet at the ALS on March 28th. Users are encouraged to bring any agenda items to me (berrah@wmich.edu) or to any other UEC member (contact information is available at http://www-als.lbl.gov/als/uec/UECcontacts.html).

7. OPERATIONS UPDATE
(Contact: RMMiller@lbl.gov)

The ALS is currently in a planned shutdown for installations and maintenance. User operations are scheduled to resume at 12:00 a.m. on Tuesday, March 21.

Long-term and weekly operations schedules are available on the Web (http://www- als.lbl.gov/als/accelinfo.html). Requests for special operations use of the "scrubbing" shift should be sent to Bob Miller (RMMiller@lbl.gov, x4738) by 1:00 p.m. Friday. The Accelerator Status Hotline at (510) 486-6766 (ext. 6766 from Lab phones) features a recorded message giving up-to- date information on the operational status of the accelerator.