[Seasonal dynamics of the content of proteins inhibiting trypsin-like proteases in the leaves of common oak (Quercus petraea Liebl.)]. / Sezonnaia dinamika soderzhaniia belkov--ingibitorov tripsinopodobnykh proteaz v list'iakh duba skal'nogo (Quercus petraea Leibl.)

After the successive purification of proteins-inhibitors of trypsin-like proteases using the methods of chromatography on DEAE-cellulose, trypsin-agarose and sephadex G-50, their numerous forms with the values of molecular weight 3.5; 6.3; 12.5; and 25.0 kDa have been found out. From spring to autumn the increase of the absolute content of proteins-inhibitors of all types was accompanied by the change of their relative content. The more than by an order increase of general content of proteins inhibitors is discussed from the position of their stress origin as a result of the effect of unfavorable ecological factors.

[Isolation and some properties of protein inhibitor of trypsin from acorns of the oak tree]. / Vydelenie i nekotorye svoistva belkovogo ingibitora tripsina iz zheludei duba chereshchatogo.

Four protein fractions with trypsin-inhibiting activity have been isolated from acorns of oak tree (Quercus robur L.) by chromatography on DEAE-cellulose. Further their purification on trypsin-agarose column have demonstrated 12 peaks of activity. Every fraction corresponded to these peaks, left the column with Sephadex G-50 with the same volume of elution that corresponded to molecular weight of 16000 +/- 10% dalton. It was concluded that they have the same protein inhibitor. All the fractions proved to be steady to high-temperature denaturation, 8 M carbamide and 0.1% SDS, but preserved not more than 20% of activity under dithiothreitol effect. All they had specificity to trypsin only and were significantly less active to chymotrypsin, peptine and pronase.

[Isolation and properties of trypsin inhibitor from the leaves of pedunculate oak]. / Vydelenie i nekotorye svoistva ingibitora tripsina iz list'ev duba chereshchatogo.

Four protein fractions inhibiting trypsin are isolated from the English oak leaves by the method of chromatography on DEAE-cellulose. Three active fractions more are found in each of them after the affinity chromatography on trypsin-agarose. Each of 12 multiple forms in the calcium-free medium contains different sets of proteins and oligopeptides possessing rather high inhibiting activity. Ca2+ being introduced to the medium, all the multiple forms somewhat increase their activity, having one peak (Mm approximately 16.5 kDa) on the column with sephadex G-50. The inhibitor possesses high indices of denaturation stability and specificity to trypsin.