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S S Puzach

Publications and source records attributed to S S Puzach.

9 recordsLinked to original sources
PubMed1989

[A method of determining the concentration of thiamine].

The rate of the production of thiazole, the first product of the reaction, catalyzed by thiaminase I (EC 2.5.1.2) from Anodonta cygnea muscles is characterized by an initial flash-up explained by a considerable difference in the rates of the enzyme-substrate complex formation and its further transformation. Basing on this phenomenon, a new method for measuring the total thiamine in vitro and in biological material has been developed. Optimal conditions for thiamine measurements in the blood and urine have been selected.

Animals↗
PubMed1980

[Direct measurement of the antivitamin action of parenterally injected thiaminase].

Thiaminase (EC 2.5.1.2) from freshwater bivalve molluscs is a polycosubstrate enzyme, which is resistant to temperatures below 55 degrees. The activation energy of the enzyme with cystein is 15077 cal/mole, with aniline--15948 cal/mole. Thiaminase when injected parenterally to albino mice 2 hrs after injection of [2-14C]thiamine causes an extensive destruction of labelled vitamin b1, which is evidenced from the [14C]thiazole content in urine, liver and kidneys. The total radioactivity and the content of [14C]thiazole in the urine samples collected within 6 hrs after thiamine injection are increased. Cysteine and histidine in combination with thiaminase have no activating effect similar to that observed "in vitro". In the experimental series when non-labelled vitamin B1 from animal tissues (liver, kidney, spleen, muscle) was substituted by the labelled one, the parenterally injected enzyme destroyed up to 30-50% of total thiamine content. Brain and skeletal muscle tissues are more resistant to thiaminase action.

Alkyl and Aryl Transferases↗
PubMedDate not supplied

[Antivitamin activity of thiaminase from freshwater bicuspid molluscs after parenteral administration of the enzyme to albino mice].

Thiaminase from bicuspid mollusc, after a single administration into mice (25 or 50 un, subcutaneously), caused a decrease in the activity of transketolase and alpha-ketoglutaric acid dehydrogenase in the animal tissues within 3 hrs. The maximal antivitaminous effect of thiaminase was manifested within 2-5 days and slightly decreased within 7 days (at a dose of 25 un). Amount of thiamin was decreased in mice liver tissue from 6.54+/-0.36 mcg/g to 4.84+/-0.23 mcg/g within the second day after the thiaminase administration. Transketolase and alpha-ketoglutarate dehydrogenase from liver and kidney were more sensitive to the antivitaminous effect of thiaminase. General condition of the animals was not altered by parenteral administration of thiaminase during a week. Thiaminase may be recommended for modelling of thiamin deficiency in animals maintained at conventional diets.

Animals↗
PubMedDate not supplied

[The presence of antithiamine factor--thiaminase--in organs of random-bred albino rats and mice].

Thiaminase activity was not found in rat and mice tissues (liver, kidney tissues) using radiometric procedure. Intact exogenous thiaminase I from bivalve freshwater mollusks was effectively detected in homogenates of rat or mice liver and kidney tissues within 6 hrs after the enzyme parenteral administration into these animals; at the same time, considerable amount of 14C-thiazol developed after thiaminase catalysis was estimated in urine.

Alkyl and Aryl Transferases↗
PubMedDate not supplied

[Characteristics of the products of thiamine degradation by molluskan thiaminase I].

Tiaminase I (EC 2.5.1.2) catalyzed degradation of thiamin in the reaction mixture free of substrate-acceptor. Thiamin exhibited properties of both substrate-donor and -acceptor of the group transferred by thiaminase I. Identification of the products developed after thiaminase reaction involving thiamin was performed using chromatography and radiometry. Kinetics of the reaction is discussed.

Alkyl and Aryl Transferases↗
PubMedDate not supplied

[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.

Alkyl and Aryl Transferases↗
PubMedDate not supplied

[The role of a cosubstrate in the kinetic mechanism of action of mollusk thiaminase I].

Mechanisms of interaction between thiaminase I and cosubstrate were studied using thiazole-2-14C-thiamine and 14C-nicotinic acid. The dissociation constant of nicotinic acid in the presence of the enzyme was of an order of 1 x 10(-6) M. A mechanism of the prestationary phase of a thiaminase reaction at -10 degrees was studied. The low temperature step, which demonstrated specific characteristics, was involved in analytic estimation of total thiamine concentration in vitro. Native thiaminase I from the bivalve mollusca Anodonta cygnea proved to be a holoenzyme.

Alkyl and Aryl Transferases↗
PubMedDate not supplied

[Approaches to assessing dynamics of permeability and duration of thiaminase I action, administered parenterally to animals].

Two approaches and direct isotopic assay were employed to examine the time course of permeability and duration of action of tissue thiaminase I injected parenterally to albino mice. The injected enzyme was found to be detectable in renal and hepatic tissues 3 hours later. The action of the enzyme dermally injected in a dose of 1.2 IU/kg in the same tissues lasted 4 days. Experimental findings led to the conclusion that the thiamine degradation enzyme may be used in experimental biology in order to estimate the duration of its action and the time course of gross molecular permeability in the tissue of test animals.

Alkyl and Aryl Transferases↗