Properties of white trunk muscle from saithe Pollachius virens, rainbow trout Salmo gairdneri and herring Clupea harengus: protein synthesis in vitro, electrophoretic study of proteins.

1. Ribosomes were isolated from white trunk muscle of saithe (Pollachius virens), rainbow trout (Salmo gairdneri) and herring (Clupea harengus). 2. Incorporation of amino acids into protein by the ribosomes was determined in systems containing liver cell sap from rainbow trout. 3. Incorporation of phenylalanine into protein was as follows: saithe 163.19 +/- 7.64 pmol, rainbow trout 126.99 +/- 3.07 pmol, herring 29.34 +/- 1.28 pmol per g wet weight of tissue and 4 min of incubation at 28 degrees C. 4. Proteins associated with the ribosome fractions showed minor differences between the species as analysed by polyacrylamide gel electrophoresis in sodium dodecylsulfate. Proteins of myofibrillar origin were predominant in those fractions.