Preputial gland -glucuronidase

The known sources which most closely approach the female-rat preputial gland in activity are the digestive juices of molluscs and of locusts. As shown for the rumen of the sheep,100 the contents of the mammalian large intestine probably owe most of their /8-glucuronidase activity to microbes, whilst in the small intestine the enzyme is probably mammalian in origin.40... 

Glucuronidase from mammalian and non-mammalian sources, including the purified enzyme from female-rat preputial gland, often displays marked inhibition in the presence of excess substrate. The number of substrate molecules per active-enzyme center in the inactive enzyme-substrate complex ig24.100. ice.167 usuaUy 2, but values of166 3 and143 4 have also been reported. 

Fig. 4.—Hydrolysis48 of 6.3 X 10-4 M Phenolphthalein 0-D-Glucosiduronic acid at Various pH Values, in 0.05 N Acetate Buffer, by a Highly Purified 0-Glucuronidase Preparation from Female-rat Preputial Gland (Section IV), Alone (X), and in Presence of 0.03 % of Deoxyribonucleic Acid (O), or of 0.01% of Albumin ( ).

The rate of removal of purified P-D-glucuronidases from rats following intravenous infusion depended on the source of the enzyme. Thus, the P-D-glucuronidase from rat serum was cleared more slowly from circulation than that from rat preputial glands. The lysosomal compartment of rat liver has an important role in the removal of circulating tris and glycoside hydrolases. ... 

The p-D-glucuronidase from the preputial glands of rats crystallized following fractional precipitation, fractionation in ethanol, and gel filtration. The purified enzyme (12S, mol. wt. 3.2 x 10 ) appeared to be homogeneous on examination by polyacrylamide gel electrophoresis, but electrophoresis in the presence... 

The preputial gland of the female rat has been recognized by Beyler and Szego (1951) as the richest tissue source of /3-glucuronidase and several attempts have been made to purify the enzyme from the gland. 

Amino acid analysis of purified (9-glucuronidase from human liver (Musa el al., 1965), bovine liver (Pkpp and Cole, 1966), and preputial gland (Ohtsuka and Wakabayashi, 1970) has been reported. Comparing this information, it would appear that three of these researchers do agree with respect to paucity of sulfur-containing amino acids. The amino acid profile of bovine liver enzyme resembled that of the preputial gland, but it was significantly different from human liver. 

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