In Science this week, investigators from Harvard University, the Dana-Farber Cancer Institute, and the Massachusetts Institute of Technology describe a method of crafting single-stranded DNA into a variety of different three-dimensional forms. Called "DNA bricks," 102 of these self-assembling structures were created from single strands of 32 nucleotide-long DNA. With intricate cavities and hollow interiors, the bricks can bind with up to four neighboring strands and be added or removed independently. Combined with DNA origami, DNA bricks could potentially be used to create nanostructures with higher yields.
Also in Science, a multi-institute team led by researchers from the University of Hamburg report on the use of a new X-ray technique to gain insights into a key enzyme in Trypanosoma brucei, the parasite that causes sleeping sickness. The enzyme, cysteine protease cathepsin B, or TbCatB, is a promising target for treating the disease, but the structure of the mature, active form of the enzyme has so far not provided enough information to design such drugs. By combining the techniques of in vivo crystallization and serial femtosecond crystallography, the investigators were able to quickly get a snapshot of the fully glycosylated precursor complex of TbCatB, which revealed the mechanism of native TbCatB inhibition, before the radiation destroyed the protein crystals.
Finally, two University of Queensland researchers discuss in Science the use of advanced genomic sequencing techniques to track the transmission of infectious diseases in health care facilities. Despite efforts such as patient isolation, disinfection, and sterilization, about 100,000 deaths occur annually due to nosocomial infections. Technological advances such as genomic sequencing, however, is poised to help tackle this problem, and the authors provide one example of how a mysterious outbreak of MRSA at UK hospital was tracked down with genomic data. "Through genomics, infectious agents can be unambiguously traced to individual patients, health care workers, and environmental niches; hence, focused infection control measures can now be adopted." Still, the appropriate protocols and "clinic-ready" software are needed to support the wider adoption of this approach.