[Immobilization of champagne yeasts by inclusion into cryogels of polyvinyl alcohol for preventing cell escape from carrier matrix]. / Immobilizatsiia shampanskikh drozhzhei vkliucheniem v kriogel' PVS, puti predotvrashcheniia vykhoda kletok iz matritsy nositelia.

Wine champagnizing, a process involving the use of champagne yeasts immobilized by inclusion into cryogels of polyvinyl alcohol, has been studied. Treatment of yeast cells with the autoregulatory factor d1 was proposed as a means of preventing the cell escape from the carrier matrix. Such a treatment inhibited growth and proliferation processes in yeasts cells, without affecting the activity of fermentation; the resulting champagne had the same organoleptic and chemical characteristics as its counterparts obtained using traditional techniques.

[Physiological and biochemical characteristics of immobilized champagne yeasts and their participation in sparkling processes]. / Immobilizovannye shampanskie drozhzhi, fiziologo-biokhimicheskie osobennosti i uchastie v shampanizatsii vin.

Methods for immobilizing champagne yeasts, physiological and biochemical characteristics of the immobilized cells, and problems of their utilization in the production of quality champagne wines are reviewed. Studies aimed at the development of efficient biocatalysts for champaignizing wines using bottle fermentation (method champenoise) and tank processing (bulk, or Charmat process), based on the use of immobilized yeast cells, are described. Data on the industrial use of such biocatalysts in countries manufacturing champagne wines are presented. Problems and prospects of further research in this field are discussed.

[Involvement of microbial alkyl hydroxybenzenes in the regulation of autolytic degradation of yeast cells]. / Uchastie mikgobnykh alkiloksibenzolov v reguliatsii avtoliticheskoi destruktsii drozhzhevykh kletok.

A comparative study was performed of the processes of autolytic degradation of the cells of Saccharomyces cerevisiae and Schizosaccharomyces pombe under conditions simulating the phase of cell death in microbial cultures: (1) during autolysis induced by oleic acid, which is the chemical analogue of factors d2 (autolysis autoinducer), (2) under the effect of extracellular microbial proteinases (enzymatic lysis), and (3) under concomitant effect of the enzymes of the endogenous autolytic complex and exogenous proteinases (heterolysis). Regulatory mechanisms controlling the rate and profundity of autolysis were elucidated, relying on the stabilization of hydrolytic enzymes and enhancement of their activity in their complexes with a chemical analogue of microbial autoregulatory factors d1, which belong to alkylhydroxybenzenes and fulfil functions of chemical chaperons. The changes in the activity of proteinases and enzymes of the autolytic complex were shown to be dependent on the concentration of the analogue at the moment of complex formation.

[Isolation of endo-1,4-beta-xylanase from Geotrichum candidum 3C with various ability of sorption on an insoluble substrate]. / Razdelenie éndo-1,4-beta-ksilanaz Geotrichum candidum 3C s razlichnoi sposobnost'iu k sorbtsii na nerastvorimom substrate.

Culture liquid from Geotrichum candidum 3C was shown to contain three endoxylanase types: endoxylanase I that binds to cellulose, endoxylanase II that sorbs to insoluble xylan, and endoxylanase III that cannot sorb to dissoluble substrate. The catalytic and substrate-binding domains of endoxylanase II were isolated.

[Isolation of highly purified cyclodextrin glucanotransferase from Bacillus sp. 1070]. / Poluchenie vysokoochishennoi tsiklodekstringliukantransferazy iz Bacillus sp. 1070]

Two chromatographic processes for purification of cyclodextringlucanotransferase (CGTase) from Bacillus sp. 1070 was carried out. The enzyme has been purified into 9.5 times on Butyl-Toyopearl and followed immobilized metal ion chromatography on Cu(II)-Iminodiacetic (IDA)-agarose. By the application of second purification scheme (chromatography on Butyl-Toyopearl and DEAE-Sephacel) the specific activity of CGTase has folded into 13.5 times. The purity of enzyme was shown to be approximately 90% by SDS-electrophoreses data. It was shown that isolated enzyme has two isoelectric points estimated as 5.1 and 5.3.

[Purification and characteristic of endo-(1--4)-beta-xylanase from Geotrichum candidum 3C]. / Ochistka i kharakteristika éndo-(1--4)-beta-ksilinazy iz Geotrichum candium 3C.

A method of purification of endo-(1-->4)-beta-xylanase (endoxylanase; EC 3.2.1.8) from the culture liquid of Geotrichum candidum 3C, grown for three days, is described. The enzyme purified 23-fold had a specific activity of 32.6 U per mg protein (yield, 14.4%). Endoxylanase was shown to be homogeneous by SDS-PAGE (molecular weight, 60 to 67 kDa). With carboxymethyl xylan as substrate, the optimum activity (determined viscosimetrically) was recorded at pH 4.0 (pI 3.4). The enzyme retained stability at pH 3.0-4.5 and 30-45 degrees C for 1 h. With xylan from beach wood, the hydrolytic activity of the enzyme (ability to saccharify the substrate) was maximum at 50 degrees C. In 72 h of exposure to 0.2 mg/ml endoxylanase, the extent of saccharification of xylans from birch wood, rye grain, and wheat straw amounted to 10, 12, and 7.7%, respectively. At 0.4 mg/ml, the extent of saccharification of birch wood xylan was as high as 20%. In the case of birch wood xylan, the initial hydrolysis products were xylooligosaccharides with degrees of polymerization in excess of four; the end products were represented by xylobiose, xylotriose, xylose, and acid xylooligosaccharides.

[Effect of protoplast formation on the antibiotic activity of the Streptomyces fradiae 165 strain--a producer of tylosin]. / Vliianie protoplastirovaniia na antibioticheskuiu aktivnost' shtamma Streptomyces fradiae 165--produtsenta tilozina.

Streptomyces is characterized by genetic instability evident from high frequency of changes in various properties of secondary metabolites occurring spontaneously or under the influence of certain factors. Protoplast formation is one of such factors. The paper is concerned with the influence of protoplast formation and subsequent regeneration into the mycelial form on antibiotic potency of S. fradiae strain 165. It was shown that protoplast formation led to changes in antibiotic potency of separate colonies and shifts in the potency in the direction of its increasing. The antibiotic potency of certain variants after protoplast formation was 2 to 2.5 times higher than the initial one. Changes due to protoplast formation of S. fradiae strain 165 were not stable and lost after 4-5 passages on agar media. Comparative restriction analysis of total DNA of the variants with different potency levels did not provide detection of changes in the genome of the strains isolated after protoplast formation.

[Optimization of protein hydrolysis by Bacillus subtilis alkaline proteinase]. / Optimizatsiia gidroliza belkov shchelochnoi proteinazoi Bacillus subtilis.

Casein hydrolysis by alkaline proteinase from Bacillus subtilis str. 72 had been investigated. It has been shown that the hydrolytic rate depends on the substrate concentration and declines rapidly with time even at low protein concentrations. It has been suggested to use an equation describing the time dependence of the rate of casein proteolysis and characterizing the optimum time of protein hydrolysis, maximum rate of hydrolysis, and the maximum yield of the reaction products.

[Coordination immobilization of fungal proteinases]. / Koordinatsionnaia immobilizatsiia gribnykh proteinaz.

The possibility of coordination immobilization of fungal enzymes from Aspergillus niger MB and Aspergillus flavipes on the styrene copolymer with maleic acid has been explored. Optimal conditions for preparing insoluble chromium-containing enzyme polymeric complexes have been studied. The synergistic effect of salts of different metals on stability of chromium-containing immobilized preparations has been demonstrated. Properties of the resultant immobilized preparations have been examined.

[Formation of higher alcohols by Saccharomyces carlsbergensis from branched-chain amino acids and their keto analogs]. / Obrazovanie vysshikh spirtov Saccharomyces carlsbergensis iz razvetvlennykh aminokislot i ikh ketoanalogov.

A new method of chemical synthesis of alpha-ketoisocaproic acid (the keto analogue of L-leucine) is described. It has been shown that the resting cells of Saccharomyces carlsbergensis 776, in the stationary state of biomass, produce mainly higher alcohols: isobutanol from L-valine and its keto analogue; optically active amylol only from L-isoleucine and its keto analogue; isoamylol only from L-leucine and its keto analogue. "Nonspecific" formation of n-propanol from L-valine, L-isoleucine and their keto analogues, as well as that of isobutanol from L-isoleucine and its keto analogue, has been also found at pH 7.0. Formation of higher alcohols from alpha-keto acids has an acidic pH optimum while that from L-amino acids has a neutral or a weakly alkaline pH optimum. Formation of isobutanol from L-valine is an exception. The dependence of higher alcohol formation on the pH and the kinetics of their accumulation suggest that higher alcohols are produced from L-amino acids in at least three sequential reactions: transamination, decarboxylation of the keto analogue being formed, and reduction of the aldehyde; formation of higher alcohols from alpha-keto acids involves two reactions: decarboxylation and reduction. Transamination and decarboxylation are limiting steps in the process in the former case, and decarboxylation in the latter.

[Effect of higher alcohols on the activity of biosynthetic L-threonine dehydratase from Saccharomyces carlsbergensis brewer's yeast]. / Vliianie vysshikh spirtov na aktivnost' biosinteticheskoi L-treonindegidratazy iz pivnykh drozhzhei Saccharomyces carlsbergensis.

The effects of low (1 . 10(-4) M) and high (1 . 10(-3) M) concentrations of n-propanol, isobutanol and isoamylols on the kinetic behaviour of "biosynthetic" L-threonine dehydratase from brewer's yeast S. carlsbergensis 776 were studied. It was concluded that these alcohols control the activity of the first enzyme of the L-threonine biosynthetic pathway.

[Effect of some amino acids on the biosynthesis of glucoamylase by cultured Endomycopsis species]. / Bliianie nekotorykh aminokislot na biosintez gliukoamilazy kul'turoi Endomycopsis species 20-9.

The effect of amino acids (glutamic, aspartic, beta-alanine, phenylalanine, methionine) on the glucoamylase biosynthesis by Endomycopsis species 20-9 was studied. Monoaminodicarboxylic acids produced a stimulating effect on the glucoamylase synthesis. Their addition at optimal concentrations of 0.2 to 0.4% increased by 54--69% glucoamylase activity of Endomycopsis sp. 20-9 upon submerged cultivation on the medium containing 3% maize extract and 1% starch. An application of this amino acid nutrition during cultivation did not produce a significant effect on the microbial glucoamylase activity.

[Effect of carbon composition of the fermented medium on the synthesis of volatile acids by the yeast Saccharomyces carlsbergensis 776]. / Vliianie uglevodnogo sostava sbrazhivaemoi sredy na protsecc obrazovaniia letuchikh kislot drozhzhami Saccharomyces carlsbergensis 776.

The effect of glucose, maltose and sucrose on the synthesis of volatile oils during fermentation of model carbohydrate solutions (6, 8 and 11%) by the yeast Saccharomyces carlsbergensis 776 was studied. The composition and concentration of carbohydrates affected the build-up of volatile fatty acids during fermentation. The accumulation of biomass and volatile fraction of fatty acids reached maximum on the medium containing 11% glucose. There was a certain correlation between the biomass synthesis and accumulation of volatile fatty acids, i.e. with an increase in the biomass the content of volatile fatty acids in the medium increased. During fermentation of disaccharide solutions cell multiplication diminished and the fermentation process accelerated. Ethanol, residual sugar and acidity of fermented solutions increased with the initial concentration of carbohydrates. The pH value of the fermented must remained essentially unaltered independent of the sugar amount used.

[Cellulase formation by soil yeasts of the genus Trichosporon and by microscopic fungi]. / Obrazovanie tselliulaz pochvennymi drozhzhami roda Trichosporon i mikroskopicheskimi gribami.

The production of celulases by a soil yeast belonging to the genus Trichosporon and by microscopic fungi of various systematic groups was studied. The yeast synthesized relatively small amounts of cellulases in contrast to microscopic fungi. The active culture producing cellulases was the fungus Trichoderma longibrachiatum 7-26.

[Purification and properties of glucoamylase from Endomycopsis sp. 20-9]. / Ochistka i svoistva gliukoamilazy Endomycopsis sp. 20-9.

Homogenous yeast (Endomycopsis sp. 20-9) glucoamylase was isolated from cultural medium. The homogeneity of the enzyme preparation is demonstrated by means of polyacrylamide gel disc electrophoresis, isofocusing and ultracentrifugation. Amino acid composition, molecular weight (53 000), sedimentation constant (4.3S) and isoelectric point (pI 3.80-3.82) of the enzyme are determined. Glucoamylase is found to be glucoprotein.

[14C incorporation into lipid fractions of yeast Candida quilliermondii during growth in the presence of different carbon sources]. / Vkliuchenie C14 v lipidnye fraktsii drozhzhei Candida guilliermondii pri vyrashchivanii kletok v prisutstvii razlichnykh istochnikov ugleroda.

Kinetics of 14C incorporation into lipid fractions of yeast C. quilliermondii from 1-14C-octadecane and 1,2-14C-acetic acid is studied. Considerable differences, revealed in kinetics and the rate of 14C incorporation into lipid fractions depending on the lipid precursors, draw to the conclusion that the lipid synthesis from octadecane and acetic acid can occur through different pathways. The absence of the competition under the carbon influx into lipid fraction also suggests, that the lipid synthesis from ocetate and carbohydrate takes place simultaneously through two different pathways, which are spatially uncoupled in cell. A presence in yeast cells of two glyoxylate shunts is proposed, which are spatially uncoupled and specific to acetyl residues of different origins.

[Influence of carbon source on lipid biosynthesis by Candida gluilliermondii]. / Vliianie istochnika ugleroda na biosintez lipidov drozhzhami Candida guilliermondii.

The biosynthesis of lipids by Candida guilliermondii was studied during the growth of the yeast on carbon substrates which resulted in different pathways of lipid biosynthesis. The highest content of lipids was found during the growth on octadecane. The quantitative ratio between fractions of neutral lipids and phospholipids depended on the carbon substrate whereas the quanlitative composition of the fractions remained the same. The fatty acid composition of lipid fractions was studied, and possible pathways of their biosynthesis are discussed. Apparently, the assimilated hydrocarbon is oxidized to acetyl residues in certain structures of the yeast cells while, in other structures, the hydrocarbon substrate undergoes only monoterminal oxidation yielding an aliphatic alcohol and an acid which are directly used in large amounts for the synthesis of wax and triglycerides.

[Effect of the physiological properties of yeast strains on their formation of higher alcohols and aldehydes and on the composition of nitrogen compounds in the fermented wort]. / Vliianie fiziologicheskikh osobennostei shtammov drozhzhei na obrazovanie imi vysshikh spirtov, al'degidov i sostav azotistykh veshchestv v sbrozhennom susle

Dynamics of formation of by-products was studied with the following yeast races: Sacch. cerevisiae, strain Odesskaya-14 (baker's yeast); Sacch. vini, strain Prikumskaya 80/9 (wine yeast). The yeast cultures were found to be very similar by the rate of biomass accumulation, ethanol production, and the fractional composition of nitrogen compounds. The concentration of accumulated higher alcohols depended on the mass of yeast cells, their growth rate, and the duration of cultivation.

[Effect of growth medium composition of glucoamylase and glycosyltransferase activity of Endomyces fibuliger]. / Vliianie sostava pitatel'noi sredy na gliukoamilaznuiu i glikoziltransferaznuiu aktinost' Endomycopsis fibuliger

Production of glucoamylase and glycosyltransferase by Endomyces fibuliger was found to depend on sources of carbon and nitrogen nutrition. Starch at a concentration above 0.5% in the medium stimulated biosynthesis of glycosyltransferase but inhibited production of glucoamylase by End. fibuliger 20-9. The rate of growth of the micro-organism increased by a factor of 3.3 with an increase of starch concentration from 0.5 to 6%. Synthesis of glycosyltransferase was repressed by glucose, lactose, sucrose and maltose. Synthesis of glucoamylase was repressed by lactose, sorbose and galactose. Synthesis of glycosyltransferase was stimulated by xylose, sorbose and galactose. Production of glucoamylase was stimulated by xylose and arabinose. Growth of the culture and synthesis of glucoamylase and maltase in the cultural broth were stimulated by an increase in the concentration of maize extract. Biosynthesis of glucoamylase and glycosyltransferase was stimulated by NH4H2PO4.