ENRICHMENT OF MYOFIBRILLAR PROTEINS FROM BEEF MUSCLE BY A SIMPLE SEQUENTIAL METHOD

ABSTRACT

A great deal of attention has been paid to the most important proteins of the myofibrillar system – myosin, actin, titin and nebulin – because of their potential role in meat processing. Several methods from different sources were reported for their isolation. However, most of them are complex, tedious and focused on the isolation of one protein at a time. In the present research, these four proteins had been co-enriched simultaneously applying a simple methodology.

Myofibrillar proteins extracted from semitendinosus beef muscles were submitted to ammonium sulfate precipitation. Titin and nebulin were precipitated predominantly in the saturation range of 40–60 g/L, and so were myosin heavy chain and actin in the range of 60–100 g/L. Denaturing polyacrylamide electrophoresis and electroelution were employed for the separation and isolation of the proteins of interest from the corresponding salt fractions. Western blot procedure was applied to detect and identify precisely nebulin band.

PRACTICAL APPLICATIONS

The described isolation method will provide enriched myofibrillar proteins, which can be used for more specific analysis or for analysis that requires a further isolated sample. For instance, these proteins could be submitted to microscopy studies, immunological and differential scanning calorimetric analysis.