Graphical analysis of flow cytometer data for characterizing controlled fluorescent protein display on λ phage

Area of Science:

• Biotechnology
• Molecular Biology
• Analytical Chemistry

Background:

• Flow cytometry is a standard tool for cell analysis.
• Native virus particles are typically too small for flow cytometer resolution.
• Fluorescent labeling is the common method for analyzing virus particles with flow cytometry.

Purpose of the Study:

• To investigate the use of flow cytometry for characterizing phage display with controlled protein expression.
• To explore data processing techniques for analyzing phage display data.
• To determine if side scatter can be used to characterize nonfluorescent protein display on phages.

Main Methods:

• Utilized a commercial flow cytometer to analyze phage particles.
• Employed a phage display strategy for controlled expression of enhanced green fluorescent protein (eGFP).
• Implemented specific data processing steps to validate observed phenomena.

Main Results:

• Phage display of eGFP led to detectable changes in side scatter and fluorescence profiles.
• Sub-populations within phage populations were identifiable.
• Side scatter analysis showed potential for characterizing nonfluorescent protein display.

Conclusions:

• Flow cytometry can be adapted to characterize phage display systems.
• Side scatter measurements offer a novel method for analyzing phage display, including nonfluorescent proteins.
• This technique provides a new avenue for understanding and engineering phage display systems.