Science Highlights & News
December 2011
Cooperative macromolecular device revealed by meta-analysis of static and time-resolved structures
Zhong Ren, Vukica Srajer, James E. Knapp, and William E. Royer, Jr.,
PNAS. 2011 Dec 14. doi: 10.1073/pnas.1109213108. [Epub ahead of print]
Here we present a meta-analysis of a large collection of static structures of a protein in the Protein Data Bank in order to extract the progression of structural events during protein function. We apply this strategy to the homodimeric hemoglobin HbI from Scapharca inaequivalvis. We derive a simple dynamic model describing how binding of the first ligand in one of the two chemically identical subunits facilitates a second binding event in the other partner subunit. The results of our ultrafast time-resolved crystallographic studies support this model. We demonstrate that HbI functions like a homodimeric mechanical device, such as pliers or scissors. Ligand-induced motion originating in one subunit is transmitted to the other via conserved pivot points, where the E and F′ helices from two partner subunits are “bolted” together to form a stable dimer interface permitting slight relative rotation but preventing sliding.
More News ›
Facility News
November 2011
Moffat Appointed Senior Advisor for Life Sciences at the APS
The Advanced Photon Source (APS) is the Western Hemisphere’s most powerful source of x-rays for research. It attracts more than 4,000 users from academia, industry, and government laboratories around the world each year for research in all fields of science. In particular, almost half of the user community is in the life sciences area. The appointment of a Senior Advisor for Life Sciences at the APS (SALSA) to provide a stronger linkage with the life sciences community has been recommended by APS review committees and has been a priority for APS management. Furthermore, ongoing preparations for a major upgrade to the APS require strategic decisions that will benefit from the advice provided by an expert in this field. Following the recommendation of a search committee composed of APS management and users, I am pleased to announce the appointment of Prof. Keith Moffat of the University of Chicago to this position.
Full story ›
More News ›
BioCARS is a national user facility for synchrotron-based static and dynamic studies of biological macromolecules, located at Sector 14 of the Advanced Photon Source, Argonne National Laboratory.
BioCARS is an integral part of the multi-institutional and multi-disciplinary Center for Advanced Radiation Sources (CARS) at the University of Chicago.
The mission of BioCARS is to develop state-of-the-art facilities and provide scientific and technical expertise and user support for studies of static and dynamic properties of macromolecules by X-ray scattering techniques such as static and time-resolved crystallography, SAXS/WAXS and fiber diffraction. The goal of research conducted at BioCARS is to understand basic biological processes in structural and dynamic terms, at the atomic resolution level. Scientific problems addressed by BioCARS users and staff are fundamental to basic science, highly relevant to significant biomedical problems and of great practical importance to the pharmaceutical and biotechnology industries.
BioCARS operates two experimental stations, embedded in a Biosafety Level 3 (BSL-3) facility.
This BSL-3 synchrotron-based capability is unique in the United States and permits safe studies of biohazardous materials, such as pathogenic human viruses.
BioCARS: a synchrotron resource for time-resolved X-ray science
Graber et al, J. Synchrotron Rad. 18, 658-670 (2011).
More about BioCARS: Facility and Scientific Mission › (PDF)
Time-resolved crystallography: past, present and future › (PDF)
Apply for BioCARS beamtime:
Submit a proposal through the APS General User Program ›
Note: BioCARS is now using the APS scheduling system for scheduling user beamtime. To submit the trip information for your scheduled beamtime, please follow the links in your beamtime notification or ESAF reminder e-mails or login to the APS scheduling system.
