Correlation of degradative rates of proteins with a parameter calculated from amino acid composition and subunit size.

A parameter is developed which relates the amino acid composition and subunit size of a protein to the degradative rate in vivo. This parameter was calculated for 11 rat liver proteins and a plot versus the half-lives of these proteins is linear and has a coefficient of correlation of -0.96. Evidence is presented which suggests that the density of excess acidic amino acids on the surface of the protein is the most important factor in determining differential turnover.