John R. Esterly

THE HISTOCHEMICAL DEMONSTRATION OF INTESTINAL β-d-FUCOSIDASE WITH 5-BROMO-4-CHLOROINDOLE-3-yl-β-d-FUCOPYRANOSIDE

Enzymatic hydrolysis of a halogen-substituted indolyl substrate for β-d-fucosidase shows a strong positive reaction in the interstitial mononuclear cells in the jejunum. This localization and the optimum pH are different from that of the analogous substrate for 3-d-galactosidase. The results of competitive inhibition of these substrates suggest that the reactions demonstrate distinct but similar tissue enzymes.

THE HISTOCHEMICAL DEMONSTRATION OF β-d-XYLOSIDASE ACTIVITY

Enzyme Nomenclature, Elsevier Pubhishimsg Company, Amsterdam, 1965, p. 140. Os-TNST bound tionspecificallv, as determined with boiled mitochotidria. The sectiomis were then staitie(l with umramiyl acetate in order to bridge uramiiuns to the osmiumns amid at the same time reveal mnitochon(lrial structure. As showmi its Fig. 2, the formazami deposits cams be seen not only as demise particulate deposits bust sometimes appear to aggregate imi a helicallike maimer with a separatiomi of 100 A betweeti coils. The presemit localization of succinic dehydrogenase activity has ample support from biochemical experimemits. It was suggested by numerous imivestigations that most of the SDH emizyme activity, if mmot all, lies its the inner membrane and cristae of the mitochondria (e.g., Chance. Proc. N. Y. A cad. Sci., 1966) vet it was tiot possible to ascertaits whether the activity was within or on the ouster surface of the membramies. Recetmtly, usitig atm osmiophilic tetrazohium salt, TC-NBT, Seligmami amid co-workers (J. Histochein. (ytochem. 15: 1. 1967; 15: 752. 1967) reported the staimiitsg on the cristae tsiembratme which emscr()ached oti the ititracristac spaces. The presemit method shows a clear imit racrist ai localization, yet makes possible high resolution electromi miiicroscopic study for numerous other problems where other methods are limited. l)etails will be reported later in a more complete paper.