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The influence of cobalt (II, III) coordinative compounds with derivatives of dithiocarbamic acid on Bacillus thuringiensis IMV B-7324 peptidases with elastase and fibrinolytic activity and Eupenicillium erubescens and Cryptococcus albidus alpha-L-rhamnosidases have been studied. Tested coordinative compounds of cobalt (II, III) on the basis of their composition and structure are presented by 6 groups: 1) tetrachlorocobaltates (II) of 3,6-di(R,R')-iminio-1,2,4,5-tetratiane--(RR')2Ditt[CoCl4]; 2) tetrabromocobaltates (II) of 3,6-di(R,R')-iminio-1,2,4,5-tetratiane--(RR')2Ditt[CoBr4]; 3) isothiocyanates of tetra((R,R')-dithiocarbamatoisothiocyanate)cobalt (II)--[Co(RR'Ditc)4](NCS)2]; 4) dithiocarbamates of cobalt (II)--[Co(S2CNRR')2]; 5) dithiocarbamates of cobalt (III)--[Co(S2CNRR')3]; 6) molecular complexes of dithiocarbamates of cobalt (III) with iodine--[Co(S2CNRR')3] x 2I(2). These groups (1-6) are combined by the presence of the same complexing agent (cobalt) and a fragment S2CNRR' in their molecules. Investigated complexes differ by a charge of intrinsic coordination sphere: anionic (1-2), cationic (3) and neutral (4-6). The nature of substituents at nitrogen atoms varies in each group of complexes. It is stated that the studied coordination compounds render both activating and inhibiting effect on enzyme activity, depending on composition, structure, charge of complex, coordination number of complex former and also on the enzyme and strain producer. Maximum effect is achieved by activating of peptidases B. thuringiensis IMV B-7324 with elastase and fibrinolytic activity. So, in order to improve the catalytic properties of peptidase 1, depending on the type of exhibited activity, it is possible to recommend the following compounds: for elastase--coordinately nonsaturated complexes of cobalt (II) (1-4) containing short aliphatic or alicyclic substituents at atoms of nitrogen and increasing activity by 17-100% at an average; for fibrinolytic--neutral dithiocarbamates of cobalt (II, III) (4-5) (by 29-199%). For increasing the fibrinolytic activity of peptidase it is better to use dibenzyl- or ethylphenyldithiocarbamates of cobalt (III), which increase activity by 15-40% at an average. The same complexes, and also compound {(CH2)6}2Ditt[CoCl4] make an activating impact on alpha-L-rhamnosidase C. albidus (by 10-20%).

Influence ofsome technological parameters of cultivation ofproducers Cryptococcus albidus, Eupenicillinum erubescens, Bacillus sp. on the process of synthesis of extracellular enzyme alpha-L-rhamnosidase has been studied. The authors have determined optimal sources of carbon (0.2-0.3% rhamnose) and nitrogen (0.2% sodium nitrate for C. albidus and E. erubescens and ammonium sulphate for Bacillus sp.) (the ratio 1:2), cultivation temperature (28 degrees C, 25 degrees C, 42 degrees C, respectively) for maximum synthesis of alpha-L-rhamnosidase. Use of the medium with initial pH value from 4 to 8 was most efficient for all the studied strains. The maximum level of alpha-L-rhamnosidase activity of E. erubescens and Bacillus sp. was established at the value of sulphite number of 0.44, while for C. albidus--it was 0.56. Maximum alpha-L-rhamnosidase activity of C. albidus, E. erubescens, Bacillus sp. is achieved at 4, 8 days and 27 hours of cultivation, respectively. The cultures being grown in selected conditions, the alpha-L-rhamnosidase synthesis has increased by 30, 50 and 20%, respectively.