We are requesting funds to purchase a Gatan K2 Summit direct electron detector that will support the research programs of nine NIH-funded investigators at the University of Texas Medical School at Houston. This detector will replace an outdated and unserviceable Tietz 4k x 4k CCD presently interfaced with a Polara G2 300 kV FEG cryoelectron microscope. This state-of-the-art K2 Summit detector has significantly improved signal-to-noise, fast read-out rates and has electron-counting capabilities that will provide investigators unprecedented resolution and throughput required for supporting high-resolution single particle, 2D electron crystallography and electron cryo-tomography projects. Data from the K2 detector will be collected on a separate high-end workstation processed through the Summit's high-speed data chassis capable of read-out rates of up to 400 frames per second. The detector will be integrated into the existing Polara G2 electron microscope and will be managed using the well-established infrastructure already in place. There is no other direct detector (or cryo-electron microscope) in the UT Health Science Center capable of supporting these projects. The total projected usage from the four major investigators is ~80%, leaving ~20% time for the five minor investigators and for supporting other new potential projects requiring cryoelectron microscopy. The Institution has made a major financial commitment of $40,000 per year for five years to support the projected maintenance costs of the new direct detector. In total, we have a cohort of well-funded NIH investigators relying on an unserviceable and out-of-date 9-year-old CCD camera. All of their research programs employ the unique advantages of cryo-EM to enable correlations between molecular mechanism and function for a host of basic prokaryotic and eukaryotic cell biological and biochemical processes that carry significant health- related impacts. The requested Gatan K2 Summit direct detector will enormously facilitate the pace of their research programs and provide structural insights not previously achievable.
