title: Changes in Calcium-ATPase Activity Associated with the Washing (Ageing) of Potato Tuber Discs.
abstract: ATPase activity in cell wall and microsomal fractions from fresh and washed potato tuber discs was measured. The activity was markedly stimulated by Ca(2+) whereas K(+) and Na(+) had little effect. The Ca(2+)-ATPase increased with washing, particularly in the cell wall fractions and in the low density fractions after discontinuous sucrose gradient centrifugation. The activities of succinic dehydrogenase and cytochrome-c-oxidase also increased with disc washing, although activity was highest in the denser regions of the gradient. A fine structural study of fresh and washed tissues revealed a pronounced increase in the membrane profile concentration of the endoplasmic reticulum and mitochondria after ageing for 24 hours.
authors.affiliation: School of Biological Sciences, University of Sussex, Brighton, BN1 9QG, U.K.
authors.forename: H
authors.initials: H
authors.lastname: Fakhrai
authors.forename: J L
authors.initials: JL
authors.lastname: Hall