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Using Microfluidics and Fluorescence Microscopy to Study the Assembly Dynamics of Single Actin Filaments and Bundles
Published on: May 5, 2022
Kinetics of filamentous phage assembly
1Institute of Microbiology and Molecular Biology, University of Hohenheim, 70599 Stuttgart, Germany.
Physical Biology
|December 15, 2010
Summary
Filamentous phages, like M13, secrete progeny without cell lysis. Supplying major coat protein (gp8) via plasmid enhances production, and M13 can infect bacteria lacking F-pili.
Area of Science:
- Microbiology
- Virology
- Molecular Biology
Background:
- Filamentous phages are non-lytic viruses that extrude progeny.
- Previous understanding of phage release mechanisms was limited.
Purpose of the Study:
- To investigate the role of the major coat protein (gp8) in filamentous phage progeny production.
- To determine if M13 phage can infect Escherichia coli lacking F-pili and secrete progeny.
Main Methods:
- Utilized plasmid-based expression of the major coat protein (gp8) with IPTG induction.
- Performed transfection of F-pilus-deficient Escherichia coli with ampicillin-resistant M13 mutant.
- Employed atomic force microscopy (AFM) and transmission electron microscopy (TEM) with gold-labeled antibodies for visualization.
Main Results:
- Phage progeny production rate was dependent on the induction of gp8.
- Successful transfection and secretion of M13 phage particles were observed in Escherichia coli lacking F-pili.
- Extruding phage particles were visualized using AFM and TEM.
Conclusions:
- The major coat protein (gp8) levels influence filamentous phage production rates.
- Filamentous phage infection and progeny secretion are possible in the absence of F-pili.
- AFM and TEM are effective methods for visualizing phage extrusion.
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