FEI Company (Nasdaq:FEIC), a leading scientific instrumentation company providing electron microscopy systems for nanoscale applications across many industries, today announced that Dr. Hong Zhou of the University of California at Los Angeles (UCLA) and the California NanoSystems Institute (CNSI) has achieved atomic resolution of viruses in solution for the first time ever recorded using a Titan Krios(TM) transmission electron microscope (TEM). The paper was published as a cover-feature in Cell (www.cell.com), April 30, 2010, Zhang et al., 3.3 Angstrom Cryo-EM Structure of a Non-enveloped Virus Reveals a Priming Mechanism for Cell Entry, Cell (2010), doi: 10.1016/j.cell.2010.03.041.
The ability to image viruses and proteins at the atomic level allows researchers to understand the structure and function of biological processes within the cell at the molecular level, thereby providing a foundation for the design of new therapeutics. The techniques used to understand the mechanism of the aquareovirus by the UCLA team is generally applicable to any virus and protein.
"We are extremely excited about the recent breakthrough achieved by Hong Zhou and his team at the Electron Imaging Center for NanoMachines (EICN)," said Dr. Leonard H. Rome, senior associate dean for research of UCLA's David Geffen School of Medicine and associate director of the California NanoSystems Institute. "The ability to understand the structure of viruses at an atomic level will open avenues for manipulating them for use in drug delivery and propel numerous innovations in treatments of diseases. UCLA is fortunate to have such specialized instrumentation, and the expertise of Professor Zhou and his team to take advantage of these marvelous microscopes."
According to Dr. Wah Chiu, professor of biochemistry and molecular biology at Houston-based Baylor College of Medicine, and one of the pioneers in the application of electron microscopy in the life sciences, "Dr. Zhou's work shows sensational structural results using single particle cryo-electron microscopy to resolve detailed protein structure in a large virus. This was thought to be impossible by many experts not long ago."
Traditional techniques, such as x-ray crystallography and NMR imaging, are capable of determining molecular structures, but usually as isolated structures and not in a cellular or physiological context. Viruses and many proteins can be difficult to crystallize, particularly those in a metastable form, so their structure cannot be obtained using x-ray crystallography. The Titan Krios was designed to overcome these challenges to enable atomic resolution imaging.
"This is a tremendous scientific accomplishment, and we are excited for Dr. Hong Zhou and his team at the CNSI at UCLA," stated Dominique Hubert, FEI's vice president and general manager for the Life Sciences Division. "It demonstrates that the FEI Vitrobot(TM) and Titan Krios TEM can be used as a workflow solution to uniquely identify atomic structures within a cell in its native hydrated state and to better understand their function."
The Titan Krios is a high-resolution, 3D imaging solution that is specifically designed to image biological structures down to the molecular, and now, atomic level in structural biology applications. Its integrated cryogenic sample handling robotics offers automation, and the solution permits a full range of high-resolution and 3D techniques including: cryo-electron microscopy; single-particle analysis; and dual-axis tomography of frozen, hydrated samples, such as viruses and molecular machines. The Vitrobot is a specimen preparation device used for plunge-freezing samples when their true colloidal structure needs to be viewed.