X-Ray Laser Pulses Reveal Key Parasite Enzyme (5 of 15) (image) American Association for the Advancement of Science Share Print E-Mail Caption Colored electron micrograph of the bloodstream form of the Trypanosoma brucei parasite (light blue) that causes African trypanosomiasis (also called sleeping sickness) in humans in the presence of erythrocytes (red) and lymphocytes (light yellow). After infection of the mammalian host by bite of the tsetse fly, the parasite lives within the bloodstream before it invades the central nervous system and the brain to cause fatal effects. This image relates to a paper that appeared in the Nov. 29, 2012, issue of Science Express, published by AAAS. The paper, by Lars Redecke at the University of Hamburg in Hamburg, Germany, and colleagues was titled, "Natively Inhibited Trypanosoma brucei Cathepsin B Structure Determined Using an X-ray Laser." Credit Image courtesy of Michael Duszenko, University of Tübingen Usage Restrictions Please cite the owner of the image when publishing. This image may be freely used by reporters as part of news coverage, with proper attribution. Non-reporters must contact Science for permission. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.