Live Bacterial Physiology Visualized with 5 nm Resolution Using Scanning Transmission Electron Microscopy
Eamonn Kennedy, Edward M Nelson, Tetsuya Tanaka
1Protochips, Inc. , Morrisville, North Carolina 27560, United States.
ACS Nano
|January 27, 2016
Summary
Researchers visualized virus infection in living cells using scanning transmission electron microscopy (STEM). This method preserves cell viability by using low electron doses, enabling nanometer-resolution imaging of viral DNA insertion.
Area of Science:
- Electron Microscopy
- Cell Biology
- Virology
Background:
- Visualizing virus-host interactions in real-time is crucial for understanding infection dynamics.
- Maintaining cell viability during high-resolution imaging presents significant technical challenges.
Purpose of the Study:
- To develop and validate a method for imaging virus infection in living cells at nanometer resolution.
- To determine the electron dose threshold for maintaining cell viability during imaging.
Main Methods:
- Utilized scanning transmission electron microscopy (STEM) with low electron doses.
- Employed positively stained Escherichia coli and P1 bacteriophages in a microfluidic liquid flow cell.
- Determined the median lethal dose (LD50) of electrons for cell survival.
Main Results:
- Established an LD50 of 30 e(-)/nm(2) for Escherichia coli, correlating with membrane disruption.
- Achieved 5 nm resolution imaging of bacteriophages and cellular structures below the LD50.
- Observed P1 bacteriophage DNA insertion into E. coli within 3 seconds at 5 nm resolution, preserving cell viability.
Conclusions:
- Low-dose STEM enables visualization of viral infection dynamics in living cells without compromising viability.
- The established electron dose threshold (LD50) is critical for balancing imaging resolution and cell survival.
- This technique offers a powerful tool for studying host-pathogen interactions at the nanoscale.
Keywords:
E. colibacteriophageinfectionliquid celllow-dose biological imagingscanning transmission electron microscopyMore Related Videos
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