Proteins: Extraction, Quantitation, and Electrophoresis

Abstract

In this laboratory exercise, sarcoplasmic muscle proteins of fish are extracted with a salt solution, the protein content of the extract is measured by the bicinchoninic acid (BCA) colorimetric assay, and the proteins in the fish extracts are separated and visualized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Visualization of the protein banding patterns (subunit size and relative quantity) makes it possible to distinguish among different types of fish since many fish have a characteristic protein subunit pattern.