Energy Dept. Helps Cast Light on Diseases

Two powerful X-ray instruments, the Linac Coherent Light Source and the Stanford Synchrotron Radiation Lightsource, are helping scientists learn more about diseases like sleeping sickness and could lead to new treatments.

Two powerful X-ray instruments, the Linac Coherent Light Source (LCLS) and the Stanford Synchrotron Radiation Lightsource (SSRL), are helping scientists learn more about diseases and could lead to new treatments.

According to the U.S. Energy Department, which hosts both instruments at one of its labs, the LCLS produces X-ray pulses so powerful that they can show structures down to the resolution of individual atoms. This sensitivity recently helped reveal the structure of an enzyme involved in the spread of sleeping sickness.

Researchers grew tiny crystals of a sleeping sickness protein in live insect cells and streamed them into the path of the X-ray laser. By mapping different intensities of light from the crystals’ diffraction patterns, shown above, scientists hope to be able to model the enzyme’s structure.

The protein used by the African sleeping sickness parasite to speed its infection is quite similar to a human protein. A precise-enough map of structures could show some essential differences between the two and enable researchers to design drugs targeting the parasite’s protein while leaving the human version untouched.

Sleeping sickness, caused by a protozoan that infects people via tsetse flies, threatens millions across Africa and kills an estimated 30,000 people every year.

The SSRL has been used by researchers to produce a 3-D image of a structure that enables the bacterium H. pylori to neutralize stomach acid. H. pylori causes stomach ulcers and can increase one’s odds of developing stomach cancer.