Weizmann Institute scientists have revealed certain mechanisms by which a mimivirus – a virus so called because it was originally thought to mimic bacteria in various aspects of their behavior – invades amoeba cells.
The mimivirus, known, among other things, for its exceptional size – it is five to ten times larger than any other known virus – was discovered only in the late 20th century, as its extraordinary size made it impossible to identify it by regular means. It contains much more genetic material than regular viruses, a feature that forces the mimivirus to develop particularly efficient methods for introducing its viral DNA into the host cell and for inserting its genetic “parcel” into a protein “container” during the production of new viruses in the host cell.
Prof. Abraham Minsky and graduate students Nathan Zauberman and Yael Mutsafi of the Organic Chemistry Department, together with Drs. Eugenia Klein and Eyal Shimoni of Chemical Research Support, have now discovered the details of some of the methods used by this virus. The scientists have obtained, for the first time, three-dimensional pictures of the openings through which the viral genetic material is injected into the infected cell, and of the process by which this genetic material is inserted into the protein container.
The study of the mimivirus’s life cycle, from cellular infection to the production of new viruses, may yield valuable insights into the mechanisms of action of numerous other viruses, including those that cause human diseases. Such insights could enable scientists to interrupt the infection cycle, blocking viral diseases.
Prof. Abraham Minsky’s research is supported by the Helen and Milton A. Kimmelman Center for Biomolecular Structure and Assembly; the Irving and Cherna Moskowitz Center for Nano and Bio-Nano Imaging; and the Wolfson Family Charitable Trust. Prof. Minsky is the incumbent of the Professor T. Reichstein Professorial Chair.