[Production of chitinase by Actinomyces kurssanovii and its properties]. / Obrazovanie i svoistva khitinazy Actinomyces kurssanovii

Actinomyces kurssanovii, a culture producing large amounts of chitinase and chitobiase, was cultivated on a medium of the following composition (%): demineralized crab shells, 3.0; K2HPO4, 0.5; peptone, 0.2; yeast extract, 0.1; MgSO4-H2O, 0.09. The maximum amount of the enzymes was synthesized after growth in a fermenter of the actinomycete during 48 hours. The highest activity of chitinase is manifested at pH 7.0 and depends on ionic composition of the buffer, being higher in veronal buffer than in phosphate or tris//HC1 buffers. The chitinase and chitobiase of the strain decompose completely colloid chitin and chitin in demineralized crab shells with the formation of N-acetyl-D-glucosamine.

[Chitinase formation by actinomycetes in deep cultures]. / Obrazovanie khitinazy aktinomitsetami pri glubinom kul'tivirovanii

Actinomycetes were cultivated in the medium containing demineralized crab shells as a source of carbon. Chitinase was found in filtrates of the cultural broth of all 44 studied strains. The activity of the extracellular chitinase was determined both by decomposition of ground chitin (CHI-activity) and colloid chitin (CHI-activity). The ratio between CHI and CHX in filtrates of the cultural broth of the most active nine strains varied from one to two.

[Study of oxidative enzymes of the lignin-degrading fungus Pleurotus ostreatus]. / Izuchenie okislitel'nykh fermentov ligninrazrushaiushchego griba Pleurotus ostreatus

The elctrophoretic separation in polyacrylamide gel of laccase and peroxidase isoenzymes of the lignin-degrading fungus Pleurotus ostreatus was investigated. The optimal electrophoretic conditions were found: in the electrode buffer tris-diethyl barbituric acid pH 7.0 in the gradient gel-4-10% acrylamide. Seven peroxidase isoenzymes oxidizing base benzidine and guaiacol were identified and five laccase isoenzymes reacting with specific substrates-p-phenylene diamine, alphs-naphthol, pyrogallol, hydroquinone were determined.

[Factors influencing the biosynthesis of beta-galactosidase in Alternaria tenuis]. / O faktorakh, vliiaiushchikh na biosintez beta-galaktozidazy Alternaria tenuis

The effect of pH, carbon sources, and some organic substances on the biosynthesis of beta-galactosidase was studied in Alternaria tenuis on a defined medium that had been optimized by the method of mathematical planning of experiments. Optimal conditions for the production of the enzyme and its liberation into the cultural broth were maintained by adding 2 per cent soya flour to the medium and 0.1 M phosphate-citrate buffer pH 3.0. The production of the enzyme was increased by 3 to 4 times. The biosynthesis of beta-galactosidase by Alternaria tenuis is of an induced nature.