[Keratinolytic activity of Streptomyces sp. 1382]. / Keratynolitychna aktyvnist' Streptomyces sp. 1382.

Research in the growth dynamics of Streptomyces sp. 1382--a producer of keratinolytic enzyme--has shown that maximum of its biosynthesis in the culture medium is achieved on the 5th day, that correlates with maximum of biomass accumulation. The enzyme complex, obtained from culture liquid, is active in the wide range of pH (4-11) and temperature (10-70 degrees C). Under such conditions it is stable and does not lose its activity during several hours. The preparation possesses different pH-optima of keratinase and total proteolytic activities: in neutral (pH 7.0) and weakly alkali (pH 8.0) regions, as well as different thermal optima at 37-40 and 50-60 degrees C, respectively. Four types of colonies whose level of keratinase activity was considerably different have been found, when analyzing heterogeneity of the strain-producer population. Study of the effect of various sources of carbon and nitrogen on proteases synthesis by the culture has found the activating effect of arabinose, maltose, peptone and yeast autolysate. Under such conditions synthesis of keratinolytic enzyme increased 6-7 time, only the sheep wool and chicken feather being added as the only source of carbon and nitrogen. The induction with substrate is discussed as a possible mechanism of keratinase synthesis regulation.

[Purification and physico-chemical properties of Streptomyces sp. 1349 collagenase and Streptomyces sp. 1382 keratinase]. / Ochystka ta fizyko-khimichni vlastyvosti kolahenazy Streptomyces sp. 1349 i keratynasy Streptomyces sp 1382.

The schemes of isolation and purification of collagenolytic enzymes of Streptomyces sp. 1349 and keratinolyte enzymes of Streptomyces sp. 1382, which include fractionation by ammonium sulphate separation on TSK-gels: ion-exchange chromatography on Toyopearl DEAE-650(M) and gel-filtration on Toyopearl HW-50, as well as highly efficient liquid chromatography. The purified enzyme preparations proved to be proteases of serine type (collagenase 2 and keratinases) as well as metalloproteases (collagenases 1 and 3). It has seen established that collagenases are enzymes of broad specificity, which are active in respect of proteins of both globular and fibrillar nature. And vice versa, keratinases are proteolytic enzymes of narrow specificity which hydrolyze native keratin. Molecular masses of purified enzyme preparations, from the data of SDS-PAAG are approximately 30-40 kDa (collagenases 1-3) and about 15-20 kDa (keratinases 1 and 2). It is shown that the charged aminoacid residues (about 85%) prevail in enzyme molecules. The enzymes are distinguished by pH- and thermooptima.

[Collagenase activity of Streptomyces sp. 1349]. / Kolahenazna aktyvnist' Streptomyces sp. 1349.

Streptomyces sp. 1349 is the active producer of collagenase. The dynamics of growth, influence of pH and temperature on collagenase activity and heterogeneity of population were studied. Maxima of the enzyme activity, proteins and biomass reach their highest point on the 3-4th day. The complex of enzymes obtained from culture liquid has pH-optimum of collagenase activity in neutral (pH 6-7) and alkaline (pH 9-10) regions, and thermooptimum at 37 and 60 degrees C. The preparation is stable. Four types of colonies with different level of collagenase activity were revealed during analysis of the heterogeneity of Streptomyces sp. 1349 population. The variant of basic type was selected for further work with activity that exceeds 2-3 times that of the control.

[Screening of collagenase and keratinase producers]. / Skryning produtsentiv kolagenazy i keratynazy.

The study of the capacity of 310 strains of microorganisms from different taxonomic groups (40 bacilli, 43 yeast, 105 streptomycetes, 12 micromycetes) to hydrolyze collagen and keratin allowed to establish that the highest level of collagenase (KA) and keratinase (KerA) activity is inherent in representatives of streptomycetes. Two strains of Streptomyces sp.--1349 and 1382 with the highest KA and KerA indices--1.9 and 1.85 un./mg of protein, respectively, have been chosen. It has been established that collagenase activity in the medium without adding the inducers decreases 4.76 times, while that of keratinase--5.71 times, i.e. the above enzymes are inducible. The investigation of the spectrum of activities has demonstrated that the both strains possess low level of the general proteolytic and elastase activities and high level of collagenase and keratinase activities. Partial purification of the enzyme complex of Streptomyces sp. 1349 by the successive precipitation by ammonium sulphate with 30, 60 and 80% saturation and a single precipitation by ammonium sulphate with 80% saturation helped to increase the level of KA 5.6-5.9 times, and that of KerA--4.2-4.5 times.