The beta-glucosidase in the gut contents of the snail Achatina achatina.
1. The enzyme beta-glucosidase (beta-D-glucoside glucohydrolase, EC 3.2.1.21) from the gut contents of active Achatina achatina exists in two molecular forms, beta-glucosidase C (mol.wt. about 82000) and D (mol.wt. about 41000). 2. Only the lower-molecular-weight species was found in the gut contents of aestivating snails or in extracts from their digestive glands and washed gut walls. 3. On re-activation of some aestivating snails, betion of ATP and Mg2+ to the isolated gut contents or to extracts from washed gut walls led to the formation of higher-molecular-weight forms of the enzyme, beta-glucosidase A (mol.wt. about 329000) and beta-glucosidase B (mol.wt. about 165000). 5. All these forms of the enzyme have similar pH optimum (pH 5.0-5.6). 6. The Michaelis constants (Km) and heat stability of the enzyme increased with increasing molecular complexity.
D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D055598:Chemical Phenomena; D002621:Chemistry; D004064:Digestive System / Q000201:enzymology*; D004956:Estivation; D005959:Glucosidases / Q000032:analysis*; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008274:Magnesium / Q000494:pharmacology; D008970:Molecular Weight; D012908:Snails / Q000201:enzymology*
D000255:Adenosine Triphosphate; D005959:Glucosidases; D008274:Magnesium