acid-phosphatase and nile-red

An integrated approach to acid phosphatase (EC 3.1.3.2) histochemistry by the azo-dye and lead-capture ('Gomori') methods in phosphate-starved hyphae of the fungus Botrytis cinerea revealed strikingly different patterns of localization of activity staining. Reaction product formed with the azo-dye method was found in numerous small organelles (<0.5 microm diameter), which also accumulated the lipophilic dye Nile Red and mislocalized the formazan indicating mitochondrial succinate dehydrogenase activity. Such small organelles were stained only weakly and sporadically with the lead-capture method; instead, lead phosphate deposits were produced mainly in large vacuoles (up to 2.5 microm diam.), similar to those accumulating the vital dye Neutral Red. Additionally, acid phosphatase activity was detected in apical secretory vesicles with the lead-capture method but not with the azo-dye method. Ultrastructural studies by transmission electron microscopy confirmed the presence of large vacuoles which showed evidence of autophagic activity, and of small moderately osmiophilic organelles. The latter are considered to be spherosomes rather than lysosomes because of their weak reaction with the lead-capture method and their high lipid content. It is suggested that their apparently strong reaction with the azo-dye method is caused partly by false localization due to the lipophilic nature of the reaction product.

Topics: Acid Phosphatase; Animals; Botrytis; Fluorescent Dyes; Histocytochemistry; Indoles; Lead; Lysosomes; Microscopy, Electron; Oxazines; Tetrazolium Salts; Tissue Fixation; Vacuoles

Fucus serratus eggs were examined for evidence of the existence of a lysosome-like body using enzyme histochemical and vital staining techniques. Simultaneous coupling azo-dye techniques for lysosomal acid phosphatase proved inappropriate owing to endogenous phenolic binding artefacts. The large number of alginate polysaccharide and polyphenolic egg vesicles interfered with vital staining techniques for lysosomes. Lysosomal esterase activity was detected in the abundant egg lipid bodies. The role of the egg lipid body as an equivalent lysosome-like body of higher plants, the spherosome, is discussed in relation to egg fertilization and early zygote development.

Topics: Acid Phosphatase; Acridine Orange; Coloring Agents; Esterases; Fluorescent Dyes; Histocytochemistry; Lysosomes; Neutral Red; Oxazines; Polysaccharides; Seaweed; Zygote