[Comparative characteristics of the metabolism of E. coli cells with various activity of penicillin acylase]. / Sravnitel'naia kharakteristika metabolizma kletok E. coli s razlichnoi aktivnost'iu penitsillinatsilazy.

A correlation between the synthesis and secretion of penicillin acylase (PA; EC 3.5.1.11) and the membrane phospholipid composition was observed in three E. coli strains. In cells with overproduction of PA, the phospholipid/protein ratio decreases, while the cardiolipin/phosphatidylglycerol ratio increases. The differences in the functioning of the electron transport system were revealed in cells with different levels of PA synthesis and secretion. The O2 consumption rate was 3 times lower in the cells with overproduction of PA than in those of less productive strains. On the contrary, membrane particles isolated from the cells of PA producers had no significant differences in the O2-reduction rate. The sensitivity of the strains to the inhibitor of terminal oxidases, sodium cyanide, and to the uncoupler of redox phosphorylation, chlorocarbonyl-phenylhydrazone, was different. Thus the E. coli cells with PA overproduction are characterized by significant changes in energetics and constructive metabolism. The interrelations between PA overproduction, phospholipid metabolism and the respiratory chain activity are discussed.

[Study of amino acid utilization by isogenic strains of Escherichia coli in relation to the culture growth and biosynthesis of penicillin amidase]. / Issledovanie dinamiki potrebleniia aminokislot izogennymi shtammami Escherichia coli v sviazi s rostom kul'tury i biosintezom penitsillinatsilazy.

Dynamics of free amino acid utilization by isogenic strains of Escherichia coli differing in intensity of their growth and levels of penicillin acylase biosynthesis in media containing corn steep liquor or peptone was studied. It was shown that in both the media some amino acids such as serine, threonine, glutaminic and asparaginic acids were actively utilized by the strains mainly during the culture intensive growth while others such as glycine, alanine and tyrosine were actively utilized during the enzyme biosynthesis. Intensively utilized arginine and proline were probably used for the growth and biosynthesis. The other amino acids were not utilized completely from the media. The lowest levels of their utilization were observed when the strains were cultivated in the medium with peptone.

[Regulation of the biosynthesis of aminoacylase and pigments by strains of Actinomyces of the genus Streptoverticillium]. / Reguliatsiia protesssov biosinteza aminoatsilazy i pigmentov u shtammov aktinomitsetnoi kul'tury iz roda Streptoverticillium.

For using actinomyceteous extracellular aminoacylase in production of optically active amino acids it is necessary to have the fermentation broth with lowered contents of extracellular pigments whose accumulation dynamics in the process of the strain growth correlates with the dynamics of the enzyme biosynthesis. The results of the studies showed that it was possible to regulate biosynthesis of the aminoacylase and pigments in the direction of increasing the enzyme production and decreasing the pigment formation by using a medium of the respective composition and providing the respective high temperature and sufficient aeration for the strains.

[Differences in the cytotoxicity mechanisms of pancreatic and microbial ribonucleases]. / Razlichie mekhanizmov tsitotoksichnosti pankreaticheskoi i mikrobnoiribonukleaz.

The effect of pancreatic and microbial ribonucleases (RNAses) on incorporation of labeled precursors, i. e. 14C-uridine, 14C-thymidine and 14C-glycine into the biopolymers of transplantable cell cultures, as well as their effect on radioactivity of the acid insoluble fraction of the cells labeled with 14C-orotic acid was studied. It was shown that the pancreatic RNAses and RNAses of Streptomyces rimosus in a dose of 1 ED50 determined by the index of the cell monolayer intactness inhibited incorporation of the labeled precursors. The inhibition was rather deep and almost equal. The enzymes lowered also radioactivity of the cells labeled with 14C-orotic acid in proportion to the time of the cell incubation in the presence of the enzymes. On the contrary, RNAses of Bacillus sp. used in analogous doses was significantly less intensive in inhibition of the precursor incorporation and almost did not lower radioactivity of the acid insoluble fraction of the cells totally labeled with 14C-orotic acid.

[Enzyme preparations for research on protein hydrolysates and amino acid mixtures not containing peptides]. / Fermentnye preparaty dlia izucheniia belkovykh gidrolizatov i smesei aminokilsot, ne soderzhashchikh peptidov.

Some properties and the hydrolysing ability of two novel enzyme preparations, a proteolytic preparation "C" from Acremonium chrysogenum (Cephalosporium acremonium) and a peptidase preparation (the producer from the family Pseudomanadaceae), are described. The preparations can be used for obtaining protein hydrolysates with different ratios of free amino acids and peptides. The protein hydrolysis with the preparation "C" enables one to obtain hydrolysates containing 13-18% of free amino acids. The further treatment of the hydrolysates with the peptidase preparation results either in complete hydrolysis of the remained peptide fractions or in obtainment of solutions containing from 60 to 85% of free amino acids and low-molecular weight peptides.

[Properties of acylase preparations from an actinomycete culture]. / Izuchenie svoistv preparatov atsilaz aktinomitsetnoi kul'tury.

A comparative study of some physico-chemical properties of high-purified preparations of extracellular penicillin-V-acylase and aminoacylase, isolated from the actinomycete Streptoverticillium No 62, revealed the difference in pH and temperature optima, in the sensitivity to the ionic composition of buffer solutions, in the enzyme stability during storage. As for the aminoacylase preparation, its thermostability was studied at different pH values, as well as the effect of specific compounds was tested. Similar to other fungal enzymes, the aminoacylase possesses a wide substrate specificity, and by its stereospecificity can be related to L-aminoacylases, while penicillin-V-acylase is a high-specific enzyme, active against phenoxymethylpenicillin.

[Isolation of a highly pure preparation of cephalexin amidase from bacteria of the genus Xanthomonas]. / Poluchenie vysokoochishchennogo preparata tsefaleksinamidazy iz bakterii roda Xanthomonas.

A procedure for highly purified cephalexin amidase of Xanthomonas was developed. It consists of preparation of a cell-free extract of the culture after cell disintegration, precipitation with ammonium sulfate, dissolution, concentration and elimination of ballast proteins, gel filtration on Sephadex G-25, sorption of ballast proteins on DEAE cellulose and chromatography on KM-cellulose. The enzyme yield is 45-55 per cent. The purity level is 80-90-fold.

[Isolation and comparative characteristics of acylase preparations from various antinomycete cultures]. / Poluchenie i sravnitel'naia kharakteristika preparatov atsilaz iz razlichnykh aktinomitsetnykh kul'tur.

The procedure for isolation of acylases from the fermentation broth filtrates of 3 actinomycetous cultures was developed with a yield of 72-97 per cent and 11-19- fold purification of the preparations. Comparative study of substrate specificity of acylase preparations showed that all of them possessed 2 types of the activity, i.e. penicillin acylase and aminoacylase cones. It was found that phenoxymethylpenicillin and acetylamino acids were the preferable substrates for revealing the hydrolytic activity of the acylases among beta-lactam antibiotics and acyl derivatives of amino acids, respectively.

[Antitumor action of RNAses modified by covalent binding with dextran m-aminobenzylhydroxymethyl ether]. / Protivoopukholevoe deistvie RNK-az, modifitsirovannykh kovalentnym sviazyvaniem s m-aminobenziloksimetilovym éfirom dekstrana.

Antitumor effect of pancreatic RNase and RNase from Actinomyces rimosus, as well as of their derivatives modified by dextran m-aminobenzylhydroxymethyl ether under different conditions was studied and compared. It was found that the efficacy of actinomycetous enzyme and its modified derivatives was superior to that of the analogous preparations of pancreatic RNase. Antitumor effect of the modified enzymes was higher than that of the native ones and depended on the modification conditions. It is concluded that biological efficacy of the RNases is determined by their origin and physico-chemical properties.

[Antiviral activity of modified RNAses]. / Protivovirusnaia aktivnost' modifitsirovannykh RNK-az.

Antiviral activity of pancreatic RNase and RNase from Act.rimosus modified by various dextran derivatives was studied with respect to aphthosa and Ayzeku disease viruses. Antiviral activity of pancreatic RNase modified by dextran m-aminobenzylhydroxymethyl ether was lower than biological activity of RNase from Act.rimosus modified by the same dextran. Antiviral activity of pancreatic enzyme modified by dialdehyde dextran also changed insignificantly. Modification by dextran hydroxyethylsulfonylanisole ether, dextran m-aminobenzylhydroxymethyl ether in the presence of pyridine or dextran sulfate resulted in a more pronounced increase in antiviral activity of pancreatic enzyme. Therefore, biological activity of the modified nucleases depended on the nature of the enzyme and dextran modifying it.

[Comparative study of the antiviral activity of pancreatic and microbial RNAse]. / Sravnitel'noe izuchenie protivovirusnoi aktivnosti pankreaticheskoi i mikrobnykh RNK-az.

The efficacy of pancreatic RNase with microbial enzymes (RN-ases) of Act. rimosus and Bacillus intermedius) was studied comparatively in vitro in a transplantable cell culture of the swine embryokidney with respect to the aphthosa virus (AV) and the virus of the Aujeszky disease (VAD). The VAD proved to be most sensitive to RNases. RNase of Bac. intermedius showed the highest antiviral efficacy. The enzymes were active in vivo, when the albino mice and newborn rabbits were infected with the AV, the RNase of Bac. intermedius being also most active in this case.

[Acylase activity of groups of actinomycetes and bacteria]. / Atsilaznaia aktivnost' nekotorykh grupp aktinomitsetov i bakterii.

The acylase activity of 113 actinomycetous strains and 71 bacterial strains was studied. A number of strains producing acylases, hydrolyzing phenoxymethylpenicillin was detected among the actinomycetous cultures and a number of strains producing acylases active against ampicillin and benzylpenicillin was detected among the bacterial cultures. These acylases may be used in production of semisynthetic beta-lactam antibiotics and their semiproducts.

[Effect of body regulatory mechanisms on the catalytic activity of exogenous enzymes]. / Vliianie reguliatornykh mekhanizmov organizma na kataliticheskuiu aktivnost' ékzogennykh fermentov.

An increase in the activity of RNAase in the organs and tissues of mice after administration of exogenous RNAases (pancreatic and actinomycetous) was studied. It was found that the increase in the RNAase activity was higher after administration of the actinomycetous enzyme. This was due to the difference in the sensitivity of the exogenous enzymes to the inhibitor of the mouse RNAase. The pancreatic RNA ase was much more senstive to the inhibitor. The capacity of the mouse blood serum to inhibit trypsin and chymotrypsin of the cattle pancreas, protease of Asp. terricola (terrilytin) and papain was also studied comparatively. It was shown that the pancreatic proteases were more senstive to the serum inhibitor. It is suggested that enzymes less sensitive to the effect of the host regulatory mechanisms (targets), i.e. enzymes of lower organisms, such as microbes and plants should be used in the enzyme therapy for increasing the catalytic activity of the host.

[Experimental study of the action of the RNAse from Actinomyces rimosus on the variolovaccine virus]. / Eksperimental'noe izuchenie deistviia RNK-azy Actinomyces rimosus na virus ospavaktsiny.

The effect of Actinomyces rimosus RNAase on the variolovaccine virus was studied. The inhibitory effect of the Actinomyces rimosus RNAase on the variolovaccine virus reproduction in the tissue culture cells was shown. In the experiments with the use of chick embryons and rabbits this effect was less pronounced. A 10 time increase in the infection multiplicity both in the tissue culture and the chick embryons had no noticeable effect on the level of the virus inhibition. It was supposed that the inhibitory effect of the RNAase on the variolovaccine was associated with impairment of the cell metabolism.

[Modification of nucleases by soluble derivatives of polysaccharides]. / Modifikatsiia nukleaz rastvorimymi proizvodnymi polisakharidov.

Preparations of pancreatic RNAase, ribonuclease Act. rimosus and nuclease Ser. marcescens covalently bound to water-soluble derivatives of polysaccharides (m-aminobenzyl-oxymethyl ether of dextran and mannan, 4beta-oxyethylsulphonylanisol, 4beta-oxyethylsulphonylaniline, 3-Cl-2-oxypropyl ethers of dextran and dialdehydedextran) have been obtained. The yields and thermal stability of immobilized nucleases depend both upon the amount and nature of the functional groups which activate the polysaccharide. Polysaccharide aminoaryl ethers capable of binding to proteins by azocoupling present special interest in view of their utilization as modifying baskings. Regulation of effectiveness of the azocoupling reaction by means of structural changes of the diazocomponent and the reaction conditions were shown. All this allows to obtain immobilized enzymes with different physico-chemical properties.

[Preparation of extracellular ribonuclease form Actinomyces rimosus 994]. / Preparat vnekletochnoi ribonukleazy Actinomyces rivosus 994.

By sequential acid treatment, gel filtration and KM-cellulose sorption a 18--20-fold purified preparation of ribonuclease with a yield of 50--60% was obtained from the culture liquid filtrate of Actinomyces rimosus 994. The preparation had a high specific activity of 450,000--600,000 units/mg protein, contained 85--98% protein, insignificant amounts of carbohydrates and hydroxytetracycline, and no quantities of DNase, phosphomonoesterases, phosphodiesterase or proteases. In RNA degradation (preparation of the total yeast RNA of the Sigma Co.) optimal results were obtained at 50 degrees C and pH 7.0--7.2 in phosphate buffer and 7.6--8.0 IN Tris-HCl buffer. The preparation was stable at high temperatures (80--100 degrees) in the wide pH range and during storage in the lyophilized form and in buffer solutions. RNase effect was inhibited by zinc, copper, iron and cobalt cations and activated by beta-mercaptoethanol, citrate and EDTA. Protamine sulphate and urea in low concentrations (0.01% and 1--4 M, respectively) accelerated and in high concentrations (1% and 8 M, respectively) terminated the enzyme reaction. With respect to many properties RNase from Act. rimosus 994 was similar to extracellular RNases, produced by other actinomycetes and fungi.

[Acylase activity of mycophilic fungi]. / Atsilaznaia aktivnost' mikofil'nykh gribov.

The acylase activity was studied with 65 cultures of mycophilic fungi belonging to 56 species and 33 genera. Among these: 9 species displayed the acylase activity toward ampicillin; 8 species, toward phenoxymethylpenicillin; 6 species, toward benzylpenicillin; and 21 species manifested the complex activity. Many of the active species belonged to the bionecrotrophic group of mycophilic fungi, the number of necrotrophic fungi was less, while that of biotrophs and saprotrophs was even lower.

[Results of a study of the pharmacokinetics of actinomycete RNAase in the bodies of white rats]. / Rezul'taty izucheniia farmakokinetiki aktinomitsetnoi RNK-azy v organizme belykh krys.

The pharmacokinetics of RNA-ase from Act. rimosus was studied on albino rats. The enzyme activity in the biological tests was determined spectrophotometrically by the increase of the acid-soluble products formed as a result of RNA-ase effect on RNA. The preparation was rapidly absorbed into the blood and organs, the maximum levels in the blood and organs being observed 30 minutes and 1 hour after the preparation administration. The preparation levels in the organs with the exception of the liver and kidneys were rather low. The highest levels observed in the kidneys and liver were 19.6 and 3.37 per cent respectively on the RNA-ase amount administered. Within the first 3 hours of the enzyme administration insignificant amounts of the substance were registered in the urine. Penetration of RNA-ase through the hemato-encephalic barrier was low.

[Characteristics of fucidin biosynthesis by a Fusidium coccineum 257 A strain]. / Izuchenie osobennostei biosinteza fuzidina shtammom Fusidium coccineum 257 A

The physiological features of Fusidium coccineum, strain 257 A, an organism producing fusidin were studied. It was found that increased concentrations of the carbon sources in the medium stimulated production of fusidin, while an increase in the content of various forms of nitrogen differently affected the level of the antibiotic viosynthesis: high concentrations of the amino acid-peptide form of nitrogen of corn-steep liquor decreased, while the protein form of nitrogen was associated with consumption of the significant part of carbon in the medium for formation of the fungus mycelium. Therefore, the concentration of the easily mobilizing forms of nitrogen may be considered as a regulator of the growth process of F. coccineum 257 A and production of fusidin by it.

[Effect of Actinomyces rimosus ribonuclease on the reproduction of viruses]. / Issledovanie vliianiia ribonukleazy Actinomyces rimosus na reproduktsiiu nekotorykh virusov

Antiviral activity of RNA-ase isolated from the fermentation broth of Actinomyces rimosus was studied. The effect of the enzyme on multiplication of the viruses of vesicular stomatitis, Newcastle and cariolovaccine diseases was investigated. It was found that the enzyme was capable of suppressing reproduction of the vesicular stomatitis virus (VSV) in the culture of chick fibroblast cells. The suppression level directly depended on the enzyme concentration and decreased with an increase in the infection multiplicity. The enzyme had no effect on multiplication of other viruses tested. RNA-ase decreased the infectious properties of the freshly isolated virus-containing material in concentrations showing the antiviral effect. Preliminary incubation of the cells with the enzyme resulted in suppression of the plaque formation by VSV. The RNA synthesis in such cultures treated with RNA-ase was somewhat lower. It was shown that the antiviral effect of RNA=ase was connected with its enzymic activity. RNA-ase has no antiviral effect in the experiments with mice infected with VSV.