Chromaffin vesieles were first purified by differential and density gradient centrifugation in isotonie (Percoll) gradients. In subsequent suerose gradients p38jsynaptophysin exhibited the same distribution as established marker substances of chromaffin vesieles. Quantification of immunoblots revealed that 750 ng p38{synaptophysin per mg of protein were present in the chromaffin vesieles reeove...

Preliminary results from differential centrifugation experiments, washing treatments, and enrichment in linear sucrose gradients at a density of 1.09 grams per cubic centimeter all indicated that beta-glucosidase activity in corn root homogenates was associated with a membrane such as tonoplast. A subsequent sucrose density gradient centrifugation time course showed that the beta-glucosidase wa...