Improving cryoEM and cryoFIB performance through amelioration of mechanical stress in vitreous ice.

Information

  • Research Project
  • 10303673
  • ApplicationId
    10303673
  • Core Project Number
    R21GM140345
  • Full Project Number
    1R21GM140345-01A1
  • Serial Number
    140345
  • FOA Number
    PAR-19-254
  • Sub Project Id
  • Project Start Date
    9/1/2021 - 4 years ago
  • Project End Date
    8/31/2023 - 2 years ago
  • Program Officer Name
    FLICKER, PAULA F
  • Budget Start Date
    9/1/2021 - 4 years ago
  • Budget End Date
    8/31/2022 - 3 years ago
  • Fiscal Year
    2021
  • Support Year
    01
  • Suffix
    A1
  • Award Notice Date
    8/26/2021 - 4 years ago

Improving cryoEM and cryoFIB performance through amelioration of mechanical stress in vitreous ice.

Project Summary/Abstract Stress introduced during vitrification has been proposed as a likely cause of two experimentally-observed methodological challenges: loss of resolution in cryo-electron microscopy (cryoEM) and attrition of lamellae milled in cryo-focused ion beam micromachining (cryoFIB). CryoEM is limited by a loss of information when the first few electrons strike, and mounting evidence points to beam-catalyzed relaxation of the built-up stress as the cause. A limitation of cryoFIB is that milled specimens break or snap during milling because of stress, but the source of this stress has not been shown. When specimens are prepared by plunge-freezing, water expands while the specimen support contracts. Additives that disrupt the open hydrogen-bonding network of water change its thermal expansivity. We will use volume-modulating excipients to change the thermal expansion coefficient of cryoEM and cryoFIB samples and eliminate mechanical stress from this source. Rheological properties of ice suggest that thermal annealing of cryoEM grids will allow solvent to flow and alleviate stress. We will warm cryoEM grids without devitrifying them to relieve stress. Therefore, our goal is to test whether volume-modulating excipients or thermal annealing will solve the problem of beam-induced motion and improve performance by 1. increasing resolution in cryoEM and 2. increasing yield in cryoFIB.

IC Name
NATIONAL INSTITUTE OF GENERAL MEDICAL SCIENCES
  • Activity
    R21
  • Administering IC
    GM
  • Application Type
    1
  • Direct Cost Amount
    150000
  • Indirect Cost Amount
    85500
  • Total Cost
    235500
  • Sub Project Total Cost
  • ARRA Funded
    False
  • CFDA Code
    859
  • Ed Inst. Type
    SCHOOLS OF ARTS AND SCIENCES
  • Funding ICs
    NIGMS:235500\
  • Funding Mechanism
    Non-SBIR/STTR RPGs
  • Study Section
    MSFC
  • Study Section Name
    Macromolecular Structure and Function C Study Section
  • Organization Name
    RUTGERS, THE STATE UNIV OF N.J.
  • Organization Department
    BIOLOGY
  • Organization DUNS
    001912864
  • Organization City
    PISCATAWAY
  • Organization State
    NJ
  • Organization Country
    UNITED STATES
  • Organization Zip Code
    088543925
  • Organization District
    UNITED STATES