Diamond Light Source
A brighter light for science
Structure of an antibacterial peptide ABC transporter
Antibiotics are important medicines for treating bacterial infections in both humans and animals, but antibiotics are losing their effectiveness at an increasing rate. Multi-drug resistant bacterial infections are becoming a huge health problem worldwide and there is a dire need for the development of new antibiotics with novel actions.
AP2 structure illuminates regulation of clathrin-mediated endocytosis
The cell’s external membrane is an impermeable barrier, made selectively permeable to some molecules (such as nutrients or chemical signals) by membrane-spanning proteins such as ion channels and receptors. The complement of these proteins at the cell surface is tightly controlled by continuous removal and replenishment. Clathrin-mediated endocytosis (CME) is a key mechanism that accomplishes this task. In CME, receptors bound to adaptor proteins such as AP2 are packaged into vesicles with the aid of a clathrin coat to form clathrin-coated vesicles (CCVs).
A structure for the enigmatic hepatitis A virus
Hepatitis A virus (HAV) targets the liver in humans, and despite the availability of a successful vaccine, there are many deaths annually caused by HAV. The virus differs from other hepatitis strains in being a picornavirus, but is also dissimilar to previously studied picornaviruses. It exists in an unusually stable envelope form in the host membrane, which makes it harder for the immune system to detect.
Visualising how nature uses vitamin B12 to deal with halogenated pollutants
A large proportion of environmental pollutants are organohalides, organic materials originating from industrial waste, which contain chlorine, bromine, or iodine. It is known that certain bacteria use vitamin B12 (cobalamin) to detoxify these halide pollutants, removing the halide through the use of key enzymes termed reductive dehydrogenases. Cobalamin is an organometallic molecule containing a cobalt ion in a cyclic organic system.
Structural and functional studies of lipopolysaccharide transport and insertion into the outer membrane by LptD/E complex
Antibiotic resistance of bacterial infections is a fast emerging global crisis and an understanding of the underlying resistance mechanisms is paramount for design and development of new therapeutic strategies. Lipopolysaccharides (LPS), which are found in the outer membrane of all Gram-negative bacteria, play a key role in antibiotic resistance. They help to stabilise the lipid membrane and provide a protective barrier that prevents toxic compounds from entering the cell. Although scientists knew which bacterial proteins were involved in the transport to and insertion of LPS into the outer membrane, the mechanism was poorly understood until now.
Inverse beam and the use of the mini-Kappa for sulphur SAD phasing on I04
Macromolecular crystallography beamlines at Diamond offer the possibility to collect accurate anomalous diffraction data at different energies on high-frame rates and noise-free detectors. These hardware advances have required improvements in both data acquisition software and automated data processing, but also the implementation of data collection strategies to allow users to accurately record their data whilst keeping up with today’s fast data collection.
SynchWeb – A Modern Interface to the ISPyB Database
This year has seen a significant upgrade to the ISPyB Laboratory Information Management System (LIMS) deployed to the Macromolecular Crystallography (MX) user community, bringing improvements for remote and local users, as well as new tools for staff members. ISPyB1 was initially developed as a collaboration between the UK, through e-HTTPx, and the ESRF, designed to deal with the large amount of information that needs to be recorded at high throughput MX beamlines.
BART – the new robotic sample changer for MX beamlines at Diamond
For more than 10 years, sample changing robots have been an essential tool for macromolecular crystallographers (MX) at synchrotron beamlines, allowing researchers to study 100's of samples per day. With the arrival of fast, pixel array detectors on all the MX beamlines at Diamond, the data collection times have reduced considerably and the number of samples being studied per eight hour shift has more than doubled in the past five years.
Three new beamlines for the village are at various stages of development. The long-wavelength MX beamline (I23) is a unique facility dedicated to directly solving the crystallographic phase problem from native proteins. It is radically different from the existing MX beamlines, with an in-vacuum sample environment and a large curved Pilatus 12M detector, bringing together cutting edge technology from different fields in science and engineering to realise this unique project. Over the last 12 months, the detector and the single-axis goniometer have been commissioned. The complex sample transfer system for moving cryogenically cooled crystals into the vacuum vessel and from an invacuum storage onto the goniometer became available in December 2014. This enabled the first in-vacuum diffraction data from protein crystals and shows the huge potential of this novel beamline. The in-vacuum sample environment in combination with the noise-free pixel-array detector yields superior signal-tonoise ratios and bodes well for the first user experiments during 2015.