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Updated: Aug 11, 2026
Green Fluorescent Protein-based Expression Screening of Membrane Proteins in Escherichia coli
Published on: January 6, 2015
Application of an Escherichia coli green fluorescent protein-based lysine biosensor under nonsterile conditions and
V Chalova1, C L Woodward, S C Ricke
1Department of Poultry Science, Texas A and M University, College Station, TX 77843, USA.
Aims:
To examine the utility of an Escherichia coli green fluorescent protein (GFP) containing biosensor for quantification of bioavailable lysine in selected feed samples under nonsterile conditions and to estimate the background fluorescence of analyzed feed samples and evaluate the risk of confounding GFP emission from the lysine assay organism.
Methods And Results:
Escherichia coli lysine auxotroph GFP based biosensor was used to determine the percentage of bioavailable lysine in two samples of soybean-, cottonseed-, and meat and bone meal under nonsterile conditions. The fluorescence emitted by GFP was successfully measured using a spectrofluorimeter to monitor bacterial growth response to protein-derived lysine and lysine containing small peptides. The autofluorescence of analyzed feed samples at different concentrations could also be estimated.
Conclusions:
When feed protein concentrations are decreased, autofluorescence interference can be avoided.
Significance:
The E. coli lysine auxotroph GFP-based biosensor can successfully be used for the determination of bioavailable lysine in these selected animal feed proteins under nonsterile conditions.
Impact Of The Study:
E. coli GFP biosensor for lysine has potential for routine application in animal feeds.
