The unusual structure of the ribosome, published online the week of July 4, 2005, in the Proceedings of the National Academy of Sciences, also suggests that the parasite has a unique scanning mechanism for translating genetic information into proteins.
"This may lead the way to the discovery or development of drugs that are specific against an essential mechanism of the life of the parasite and do not affect the infected organism," said parasitologist Mariano Levin, an HHMI international research scholar at the Institute for Research on Genetic Engineering and Molecular Biology in Buenos Aires and co-author of the study.
Levin met senior author Joachim Frank at a science meeting at HHMI headquarters in Chevy Chase, Maryland. Frank is an HHMI investigator at Health Research Inc., at the Wadsworth Center in Albany, New York, who had pioneered the analysis of ribosome structures by a method he developed for three-dimensional reconstruction of large molecules using electron microscopy and image processing. Levin told him the story of Chagas and the need to know more about the structure of the parasite's ribosome.
A ribosome is basically a double ball made mostly of RNA and over 50 proteins. The balls, which are of unequal size, are called small and large subunits. After a string of messenger RNA (mRNA) copies the information encoded on a gene, it enters a sea of ribosomes, where that genetic information is translated into a protein product.