in roots epicotyls and leaves of 5-, 6-, and 7-week-old Brassica seedlings were studied. No variation in isoesterase phenotypes was found between individuals within the examined cultivar. Differences in the number and intensity of isoesterase bands between the investigated organs were observed. Distinctive isoesterase patterns were evaluated for each organ. Some esterase isoenzymes are proposed as markers of particular organs: EST 1/1 and EST 1/2 for leaves, whereas EST 2/2 and EST 2/3 for roots. Further studies be aimed at using different organo-specific isoesterase forms as markers of early stages of in vitro organogenesis in Brassica callus tissue culture.
Pig liver esterase (PLE) is widely used as a biocatalyst in organic synthesis. The model of PLE catalytic center is discussed. Simple experimental procedure providing gram quantity of this enzyme is introduced. General aspects of PLE reactivity and selectivity are presented. The most representative chemical reactions catalyzed by PLE are shown on selected examples.
Total proteins, esterases and acid phosphatases from pollen, seeds and leaves of three sunflower cultivars were separated by 2-D electrophoresis. The characteristic peptides for each cultivar were identified. The seeds and pollen of the cultivar Wielkopolski contained 45 and 37 characteristic peptides, respectively, while the seeds and pollen of Coril contained 73 and 35 characteristic peptides. The cultivar Frankasol had the lowest total number of stained peptides in seeds and pollen, and the number of the characteristic peptides was only 61 and 25, respectively. Analyses of esterases and acid phosphatases from young leaves and pollen led to identification of isoenzymes characteristic of the three cultivars. Only for Frankasol no specific acid phosphatase was observed, both in leaves and in pollen.
The paper reviews fluorescent staining techniques allowing to diagnose the physiological state of bacterial cells. Different staining probes and a manner of their use for analysis of cell viability, membrane potential, membrane integrity, intracellular pH, respiratory activity, amount of nucleic acids, and activity of chosen intracellular enzymes are described. Range of examples of fluorescent staining for monitoring of physiological state of bacteria in natural environment and in biotechnological processes are presented.
Thyroxine is known to play an important role during the developmental process of amphibians. The present work is designed on the hypothesis that a functional relationship exists between the thyroid gland and digestive physiology in the adult toad. Three doses of thyroxine (25 mug/100 g; 50 mug/100 g; 100 mug/100 mug body weight) were orally dministered daily to the adult male toad, Bufo melanostictus and changes in -amylase, pepsin, trypsin, and esterase activities of the different zones of the digestive tract, pancreas and liver were observed. The observations were made on 7, 15, and 30 days of thyroxine treatment. The result shows that the dose of 25 mug increases the enzyme activities in the gastrointestinal tract, liver and pancreas of 7 days treatment. However, prolonged treatment with all the doses shows little effect on these enzymes. The pattern of changes in the enzymatic activities in the digestive tract of the adult male toads show more advanced compartmentalization than that of fishes. It is also found that site-specific enzyme production is not pronounced in this amphibious vertebrate. It is proposed that a positive functional relationship between thyroxine and digestive enzymes exists in the adult male toad.
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