X-Ray Laser Pulses Reveal Key Parasite Enzyme (3 of 15) (image) American Association for the Advancement of Science Share Print E-Mail Caption Representation of a magnified tsetse fly, the biological vector of the Trypanosoma parasite. During the feeding process, the parasite is transmitted by the fly from infected to uninfected vertebrate hosts. After uptake of the trypanosomes from an infected human, the parasite reproduces itself within the tsetse fly, representing the sexual phase of the trypanosome life cycle. After several replication cycles, the parasite is again transferred to vertebrates. 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.