Although the desire to streamline was paramount along with a responsive display that works across multiple devices, we wanted to visually highlight our users and scientists in action at the lab and sprinkle their news articles across the site. We chose a CMS platform, Drupal 8, which in addition to those and many other engaging digital experience features, allows for accessible content entry. The results of the project were revealed last month.
Like many other bacteria, Rickettsia uses the actin cytoskeleton of the host cells to move within a cell and spread from one cell to another. It does this through the agency of a “comet tail” assembled from actin filaments, and inhibition of comet tail formation reduces the virulence of Rickettsia. The bacterial transporter protein Sca2 is required for assembly of comet tails; it functions similarly to the eukaryotic formin proteins in promoting actin filament formation.
Insight into this question has biomedical significance, as membrane proteases are required for the cleavage of transmembrane anchors to release signaling proteins from the membrane, and disruption of this process is implicated in more than a dozen diseases. For example, the intramembrane rhomboid proteases are implicated in Parkinson's disease and parasite invasion.
Electrostatic interactions are important for both phases, and conformational changes occurring in an enzyme during its catalytic cycle modify these interactions. For complete understanding of the catalytic process, we require knowledge of the contribution of electrostatic effects to each step in the process, as well as an understanding of how conformational changes affect the electrostatic environment in the active site.
Professor Arnold, a long-time user of CHESS and MacCHESS facilities, was honored for his research in macromolecular crystallography and drug design targeting infectious disease agents. Also cited were his contributions to the field through scholarly and organizational activities, including serving on advisory boards for macromolecular crystallography and synchrotron radiation. Arnold was among eight ACA Fellows named this year, bringing the total to 35.
As support for CHESS shifts from NSF to include other partners, CHESS will evolve from a general user facility to a facility supporting the partners’ research programs. This will necessarily entail a shift in CHESS’s user community and programmatic focus. Nevertheless, there are aspects of CHESS that will always remain intact:
Nimbleness: Over and over again, CHESS has demonstrated the ability to respond quickly to opportunities and challenges. By way of example, it typically takes CHESS 12-18 months – from concept to commissioning – to rebuild and upgrade an x-ray beamline and restore it fully to user operations.
Cost Effectiveness: The typical cost for CHESS to upgrade an x-ray beamline (including insertion device and x-ray optics) ranges from $1M to $2M.
Innovation: CHESS has a long tradition of inventing and developing novel technologies and techniques which then find wide adoption in the international synchrotron community. Recent examples developed under the current CHESS award include: the high performance, cost-effective Cornell Compact Undulator (a variant known as the “after burner” produces circular and elliptically polarized x-ray beams at the LCLS enabling studies of magnetism); the lithographically fabricated Cornell Collimating Arrays which enable non-destructive, 3D x-ray fluorescence imaging and are in use at APS, CLS, and PETRA-III; and, the user-friendly and popular RAW suite of programs which support data processing and analysis for BioSAXS has been downloaded over 4000 times in 2017.
User Service: A consistent refrain from CHESS users is their deep appreciation for what they call “The CHESS experience.” In practice this means consistent and in-depth interactions between users and CHESS scientists and technical staff beginning in the pre-proposal stage and extending through experimental development, data collection, analysis, and interpretation. This is equally valuable to novice users, to users from non-traditional synchrotron disciplines, and to expert users working on novel experiments.
New Users: CHESS has a demonstrated track record of developing both entirely new scientific communities using synchrotron x-rays (recent examples include Structural materials, BioSAXS and Plantphenotyping) and novice users within scientific disciplines with well-established synchrotron communities.
As support for CHESS shifts from NSF to include other partners, CHESS will evolve from a general user facility to a facility supporting the partners’ research programs. This will necessarily entail a shift in CHESS’s user community and programmatic focus. Nevertheless, there are aspects of CHESS that will always remain intact:
This is especially important when illuminating very small samples, as in protein microcrystallography where crystals can be on the order of a micron across and diffract weakly compared to larger crystals. Any excess scatter in these conditions will contribute unwanted noise and decrease the overall signal-to-noise ratio – an important measure of data quality. Consider an experiment where you first must take the water from a firehose and somehow get a water thread thinner than a human hair without any mist! That is akin to the scale of creating x-ray microbeam at CHESS.