Surface Protein Quantitation
Surface Protein Quantitation - Related Videos
07:42
In-vivo Detection of Protein-protein Interactions on Micro-patterned Surfaces
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Cited by 7 •
2010
This video shows experiments with subsequent analysis of protein-protein interactions by the use of micro-patterned surfaces. The approach offers the possibility to detect protein interactions in living cells and combines high throughput capabilities with the possibility to extract quantitative information.
10:35
Surface Passivation for Single-molecule Protein Studies
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Cited by 270 •
2014
We describe a method for passivating a glass surface using polyethylene glycol (PEG). This protocol covers surface cleaning, surface functionalization, and PEG coating. We introduce a new strategy for treating the surface with PEG molecules over two rounds, which yields superior quality of passivation compared to existing methods.
11:12
Identification of protein complexes with quantitative proteomics in S. cerevisiae
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Cited by 4 •
2009
Here we describe a new quantitative proteomics technique for identifying protein complexes in Saccharomyces cerevisiae. In this study, we have used the SILAC method together with affinity purification followed by tandem mass spectrometry to identify with high specificity the binding partners of an ER protein, Scs2p.
04:39
Quantitative Dot Blot to Estimate Target Proteins in a Tissue Lysate
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2025
This video demonstrates a quantitative dot blot, or QDB, technique for the absolute quantification of proteins of interest in a tissue sample. The proteins in the sample are immobilized on the nitrocellulose membrane inside the wells of a QDB plate. Utilizing target protein-specific antibodies labeled with a peroxidase enzyme, a chemiluminescent substrate is oxidized to produce light, which is measured to determine the protein concentration of the sample.
10:50
Qualitative and Quantitative Assays for Detection and Characterization of Protein Antimicrobials
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Cited by 11 •
2016
Here, we present protocols to rapidly screen and characterize enzymes for antimicrobial activity. The microslide diffusion assay and the dye-release assay utilize target bacterial substrates for qualitative and quantitative enzymatic activity evaluation.
FAQs
A labeled antibody recognizes a specific extracellular epitope, meaning the exposed portion of the target protein. Binding places the detectable label at the cell or microorganism surface, and the resulting signal reflects the amount of recognized target available for measurement. Flow cytometry or another detection method then records that signal for comparison across samples.
Calibration standards provide a reference for converting measured signal into an estimate of protein abundance. Without that comparison, results may primarily indicate relative signal differences between samples. Using standards strengthens quantitative comparisons and helps distinguish changes in the amount of a surface protein from a simple observation that the protein is present.
They can show how surface abundance changes between cellular states, samples, or experimental conditions. In immunology, those differences may help characterize receptors associated with immune-cell identity, activation, or differentiation. In infection studies, measuring pathogen surface antigens can indicate how surface features vary during host-pathogen interactions and support investigation of disease mechanisms.
The same measurement principle can be applied to distinct targets: an antibody identifies an extracellular epitope, and the measured signal is interpreted against calibration standards. For immune cells, the target may be a receptor related to activation or differentiation. For microorganisms, it may be a surface antigen, allowing investigators to compare biologically different systems using quantitative surface information.
A typical workflow selects a labeled antibody directed against the desired extracellular epitope, allows binding to the cells or microorganisms, and measures the resulting signal by flow cytometry or another detection method. The measured values are then compared with calibration standards to estimate surface-protein abundance and support comparisons among samples.
The approach is useful when researchers need to characterize immune-cell receptors, follow activation or differentiation, detect pathogen surface antigens, or examine changes during host-pathogen interactions. Because it produces quantitative estimates rather than only descriptive observations, it can contribute to studies of disease mechanisms, diagnostics, and responses to therapeutic interventions.