**** **** **** * * * * * * **** **** **** * * * * * * **** **** * * **** HEADLINES - a digital monthly publication
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Contents of This Issue:
1. SPEAR2 is Still Going Strong!
(contact: Ed Guerra - guerra@ssrl.slac.stanford.edu)
We are happy to report that in our efforts to prepare for SPEAR3 construction during the recent shutdown, we did not break SPEAR2. The FY2001 run, which saw first users on-line on November 1, 2000, has come off to an excellent start, with experiments running successfully on every station. The idle RF station tuners are parked in a new position and the beam has been remarkably stable since. The run started with two fills per day and, as expected, lifetimes have improved to the point where fills are now being scheduled only once a day. The injector is performing very well also, with injection turn around time averaging 18 minutes. To date, SPEAR has delivered 96.4% of the 507 hours scheduled for users. With the installation of the "magic fingers" module BL11 is operating regularly at its full 2 Tesla field. We are planning about 8-9 months for user operation during this run cycle, scheduled as usual in three segments, with a summer shutdown starting around mid-July 2001.
2. The SSRL Proposal Review Panel Welcomes a New Member
As mentioned in the August edition of Headlines, Doug Rees' tenure on the Proposal Review Panel came to an end this summer after 11 years of dedicated service. We are pleased to announce that Chris Hill has accepted our invitation to serve on the Structural Molecular Biology & Biophysics subpanel of the PRP.
Chris is a professor at the Department of Biochemistry of the University of Utah. His laboratory focuses on the study of structure and function of proteins with a goal of understanding the biochemical mechanisms that are responsible for the regulation of biologically important systems such as heme biosynthesis. He is especially interested in the assembly, the function and the motion of multi-protein complexes such as the proteasome pathway, HIV assembly, and the bacterial flagellar motor.
3. X-ray Absorption Spectroscopy - Insights into Molecular Toxicology
(contact: Graham George - george@ssrl.slac.stanford.edu)
X-ray absorption spectroscopy carried out at SSRL is featured in the cover article of the November issue of the American Chemical Society publication Chemical Research in Toxicology [13(11), 1135-1142]. Entitled "Structural Basis of the Antagonism between Inorganic Mercury and Selenium in Mammals", the paper addresses the intriguing but paradoxical fact that co-administration of large doses of potentially toxic sodium selenite counters the toxic effect of mercuric chloride. Se and Hg EXAFS revealed the presence of an apparently mercuric-selenide core complexed with sulfur, which is thought to bind to selenoprotein P in blood. This work was a collaboration between the University of Arizona (Jürgen Gailer, Sean Madden, M. Bonner Denton, Husam S. Younis, H. Vasken Aposhian), ExxonMobil (Roger C. Prince) and SSRL (Graham N. George, Ingrid J. Pickering, Eileen Y. Yu).
4. A New Face in the User Research Administration
(contact: Dave Dungan -
dungan@ssrl.slac.stanford.edu)
As you may be aware, both Marjorie St. Pierre and Audrey Archuleta left SSRL and California for other activities this summer. In mid-November, SSRL welcomed Cathy Knotts aboard as the new manager of User Research Administration. Prior to joining us, she spent a number of years at the NIH and in the non-profit corporate arena. Cathy brings a wide range of administrative experience including program management and research administration. Lisa Dunn, who one user has described as "having been at SSRL forever" and knows very well how we do business, has assumed primary responsibility for the macromolecular crystallography proposal review process, scheduling and user interaction. Cathy and Lisa will work closely together to provide the best possible interface to the user community and serve your needs.
5. SSRLUO Executive Committee Election Results
We would like to thank those members of the SSRL User Community who took the opportunity in October to vote for new members of the SSRL Users' Organization Executive Committee. We are also very appreciative of the service given to the organization by those members who have just rotated off the committee including, Bernhard Rupp (LLNL), David Salt (Northern Arizona University), Sam Traina (Ohio State University) and Tom Trainor (Stanford University) and we extend our thanks on behalf of the larger User Community. In their place, you have elected, Satish Myneni (Princeton University), John Peters (Utah State University) and Vittal Yachandra (LBNL) representing the areas of environmental/geosciences, macromolecular crystallography and structural molecular biology, respectively. Lipika Basumallick (Stanford University) has been elected to the student position. The election results were very close, which we believe is a reflection of how well all of the nominees are thought of in their respective peer groups.
Thanks also to Bruce Clemens (Stanford University) who has passed the important job of chairperson to Paul Foster (Exelixis). SSRL staff and management look forward to working closely with Paul and the Executive Committee to address issues of concern to the user community and obtain guidance and input on further development of the lab and its facilities.
(for a full FY2001 SSRLUO-EC contact list see: http://www-ssrl.slac.stanford.edu/users/ssrluo/ssrluoec-FY01.html)
6. New Mirror for Powder Diffraction Beam Line
(contacts: Bart Johnson - bart@ssrl.slac.stanford.edu,
John Arthur - jarthur@slac.stanford.edu,
Apurva Mehta - mehta@ssrl.slac.stanford.edu)
Beam Line 2-1, which is primarily used for x-ray powder diffraction, received a major upgrade during the summer of 2000, with the installation of a new focusing mirror and mirror mover. The old mirror was degraded by radiation damage, and its positioning mechanism was far from the current state-of-the-art. The new mirror, made from a single crystal of silicon and coated with a platinum reflecting surface, is designed to be compatible with the power coming with SPEAR3 operation. Its positioning mechanism uses up-to-date stepping motors and drivers. First measurements show a significant improvement in beam line performance with the new mirror: the focal spot is less than half as large as that obtained with the old mirror, and yet the focused flux is more than 2.5 times greater. Further improvement is expected later this year with the installation of adjustable slits in front of the new mirror. New users interested in taking advantage of the excellent characteristics of this BL for powder diffraction studies are encouraged to contact one of us.
SSRL Headlines is published electronically monthly to inform SSRL users, sponsors and other interested people about happenings at SSRL. SSRL is a national synchrotron user facility operated by Stanford University for the U.S. Department of Energy Office of Basic Energy Sciences. Additional support for the structural biology program is provided by the DOE Office of Biological and Environmental Research, the NIH National Center for Research Resources and the NIH Institute for General Medical Sciences. Additional information about SSRL and its operation and schedules is available from the SSRL WWW site: http://www-ssrl.slac.stanford.edu/
You can subscribe or remove your name from the distribution list by sending a brief email with your request to Lisa Dunn, editor, at lisa@ssrl.slac.stanford.edu.
