Fluorescent Reporter Probes
Fluorescent Reporter Probes - Related Videos
03:04
Generation of a Fluorescent Reporter Strain in Pseudomonas aeruginosa
0 Views •
2025
Source: Rugjee, K. N. et. al., Establishment of a High-throughput Setup for Screening Small Molecules That Modulate c-di-GMP Signaling in Pseudomonas aeruginosa. J. Vis. Exp. (2016)This video demonstrates the generation of a cyclic-di-GMP-responsive reporter strain in Pseudomonas aeruginosa using electroporation. Successful transformation is confirmed through antibiotic selection and fluorescence-based...
02:59
An In Vitro Assay for Measuring Neutrophil Serine Protease Activity Using a Fluorescent Reporter
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2025
This video demonstrates an in vitro assay to quantify neutrophil serine protease activity in sputum samples. The sample containing secreted protease is incubated with a fluorescent reporter bearing a recognition motif. Cleavage of the motif by the protease enables individual fluorescence emission by the donor and acceptor fluorophore of the reporter, indicating protease activity in the sample.
04:02
An Assay to Measure the Accumulation of a Fluorescent Antibiotic Probe in Bacterial Cells
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2025
This video demonstrates an assay to measure the accumulation of a fluorescent antibiotic probe in bacterial cells. Exposure to an efflux pump inhibitor disrupts the transmembrane proton gradient in bacterial cells, upon which a fluorophore-conjugated antibiotic is added. Inhibition of efflux pumps due to the disrupted proton gradient causes accumulation of the antibiotic inside the bacteria. Bacterial cells are lysed, and the fluorescence intensity is measured to confirm antibiotic accumulation.
10:59
Determination of Lipid Raft Partitioning of Fluorescently-tagged Probes in Living Cells by Fluorescence Correlation Spectroscopy (FCS)
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Cited by 9 •
2012
A technique to probe the lipid raft partitioning of fluorescent proteins at the plasma membrane of living cells is described. It takes advantage of the disparity in diffusion times of proteins located inside or outside of lipid rafts. Acquisition can be performed dynamically in control conditions or after drug addition.
02:45
Assessment of Viral Fusion Inhibitors Using a Cre-Inducible Fluorescent Reporter
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2026
Source: Esposito, A. M.,et al. High-throughput Cre-Lox Activated Viral Membrane Fusion Assay to Identify Inhibitors of HIV-1 Viral Membrane Fusion. J. Vis. Exp. (2018)This video demonstrates a co-culture fluorescent assay to monitor cell-to-cell viral transmission. The assay uses a red-to-green reporter cassette to visualize viral membrane fusion and evaluate the efficacy of test compounds in blocking viral entry.
FAQs
The signal depends on how labeling chemistry couples recognition to fluorescence. A fluorophore may change its environment after binding, become separated from a quencher, or become concentrated where the target is located. These mechanisms convert a molecular recognition event into a detectable change, allowing target-associated signal to be distinguished from the probe’s unbound state in a complex sample.
Complementary nucleic-acid recognition gives sequence-level selectivity: hybridization occurs when the probe encounters the matching sequence. That selectivity helps distinguish a target within a mixture of biological molecules, while the linked fluorophore supplies the measurable readout. In infection studies, this pairing connects molecular identity with a signal that can be localized or quantified.
Signal localization is not merely a visual feature; it links fluorescence to the position of the recognized molecule. When binding concentrates signal at a target, researchers can assess where that target occurs within a sample rather than only whether fluorescence is present. This spatial information is especially relevant when studying pathogen distribution or interactions involving immune cells.
A basic workflow begins by selecting a biological target and using a probe whose recognition component can bind that target. The labeled probe is then examined in a complex sample with an appropriate fluorescence readout. Depending on the question, researchers measure signal through microscopy, flow cytometry, or a quantitative assay to determine target presence, location, or amount.
Microscopy is suited to visualizing where fluorescence appears and can reveal spatial relationships in a sample. Flow cytometry provides fluorescence measurements associated with individual cells, supporting analysis of cell populations. Quantitative assays are useful when the goal is a numerical readout rather than an image. The choice therefore depends on whether location, cellular distribution, or measurement is central.
In infection research, target-specific fluorescence can support detection in complex samples and help determine where pathogen-associated targets occur. A probe may therefore contribute both an identification signal and a localization readout. These capabilities support infection diagnostics, studies of pathogen distribution, and comparisons of fluorescence associated with different biological samples or experimental conditions.