Quantitative Enzyme Cytochemistry in Plant Biotechnology

Immunocytochemistry, one of the two basic approaches to the in situ study of enzymes, allows the enzyme molecules to be localized, but indicates nothing about their activity. Quantitative cytochemistry, on the other hand, indicates the sites of localization of enzyme activity and, in many cases, the rates of these activities. This latter approach, which is the subject of this review, permits the assessment of activity in individual cells or groups of cells in a given tissue. Details of tissue preparation, enzyme procedures, methods of quantification and some case histories illustrate the specificity and flexibility of the method.