Published online by Cambridge University Press: 14 April 2009
Three acid phosphatase allozyme strains (Acph-1, Acph-2 and Acph-4) of Drosophila virilis show large differences of enzyme activity when examined by means of starch gel electrophoretic technique, Acph-4 strain showing approximately four times the activity of Acph-1 and twice that of Acph-2, as reported previously (Narise, 1976). Crude extract difference between Acph-4 and Acph-1 strains is less than twofold and this compared with larger differences in supernatants. Cell fractionation and density gradient centrifugation demonstrated that the acid phosphatase resides mainly in lysosomes and becomes soluble in part during preparation without structural damage to lysosomes. The solubility of the allozymes from lysosomes was variable among the three strains. ACPH4 allozyme was released in the highest degree. However, the release-rate of other lyso-somalenzymes, such as α-glucosidase, β-galactosidase and β-glucuronidase was similar among these strains. These results suggest that the strain variation in ability of the allozymes to be incorporated into lysosomes is due to the allozymes themselves, not due to alteration in the lysosomes.