FEULGEN CYTOPHOTOMETRY OF PINE NUCLEI .2. EFFECT OF PECTINASE USED IN CELL-SEPARATION

Pectinase used for cell separation prior to cytophotometry contains a DNase that is able to penetrate the cells of pine root tips and attack nuclear DNA. When pine root tips were exposed to 1% pectinase (pH 6.0), there was a decrease in nuclear DNA content at every sample point and a sharp drop between 16 and 20 hr. The effect of the DNase was eliminated by preparing the enzyme solution in 0.01 M sodium citrate or 0.001 M EDTA. It is suggested that hut denaturation of the DNase should also be effective and might be used in combination with the magnesium chelators. © 1979 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.