[Antivitamin activity of thiaminase from B. thiaminolyticus with different routes of administration into animals].

Effect of bacterial thiaminase was studied in vivo after subcutaneous and intragastric administration of either the enzyme or of suspensions of intact and inactivated with an antibiotic bacterial cells, producing thiaminase. Activity of the thiamin-dependent enzymes (transketolase and alpha-ketoglutarate dehydrogenase) was distinctly decreased in liver and kidney tissues within 2 and 7 days after a single subcutaneous administration of 0.015 IU of the enzyme. Repeated administration of the enzyme within 4 days inhibited activity of thiamin-dependent enzymes in other tissues (heart, spleen, muscle and blood). Activity of thiamin-dependent enzymes in liver, kidney, heart, spleen, brain, muscles and blood was decreased more distinctly after administration of intact bacterial cells into mice stomach as compared to the effect of inactivated cells. Old animals were more sensitive to administration of intact bacterial cells than the young ones. The data obtained suggest that, besides the known thiamin-degrading effect of bacterial thiaminase in the intestinal contents, the enzyme exhibits functional activity within the animal tissues after the parenteral administration.