Rupture of rat liver lysosomes mediated by l-amino acid esters

Treatment of rat liver lysosome suspensions with 0.5–20 mM α-l-amino acid esters results in a progressive loss of latency of lysosomal enzyme activity. The increase in available acid phosphatase activity in lysosomal suspensions is correlated with the decrease of turbidity of these suspensions. Ester mediated turbidity decrease is dependent upon ester concentration, and the pH and ionic strength of the suspending medium. d-Stereoisomers of amino acid esters do not exhibit comparable capacity to damage lysosomes.α-l-Amino acid esters were found to be substrates for neutral lysosomal esterase and transpeptidase activity. The d-stereoisomers are degraded at much lower rates. These data support the hypothesis that ester dependent lysosomal rupture is mediated by the specific interaction of the ester with a structural or functional lysosomal protein.