Effect of microelements on formation of acids and ethyl alcohol by Saccharomyces carlsbergensis yeasts]

The effect of Fe, Zn, Mn, Pb, Al, Cu, and K on the synthesis of pyruvic, alpha-ketoglutaric and total volatile acids and ethanol was studied in the process of fermentation of 6 per cent maltose solution by Saccharomyces carlsbergensis 776. Experiments were conducted using techniques of their mathematical planning. Fe, Pb, and Mn at concentrations of 15.0, 0.5, and 1.5 mg/litre, respectively, had a positive effect on the synthesis of pyruvic acid whose concentration in the medium increased by 3.3 mg per 100 ml to become equal to 43.3 mg per 100 ml. Fe3+ at a concentration of 15 mg/litre had a negative effect on the synthesis of alpha-ketoglutaric acid. The synthesis of volatile acids depended on the presence of Fe, Zn, Pb, Al, and K. Fe and Al at concentrations of 15 mg/litre favoured the synthesis of volatile acids by 2.72 mg/litre. In the presence of Zn (1.5 mg/litre), Pb (0.5 mg/litre), and K (15 mg/litre), the content of volatile acids decreased by 4.48 mg/litre and became equal to 14.94 mg/litre. Zn at a concentration of 1.5 mg/litre inhibited it.     

Study on the usefulness of hypertonic culture media

Specimens from 300 patients were studied using five to nine aerobic and anaerobic culture media, including five that were hypertonic, Groups studied included fever of unknown origin, suspected endocarditis, endocarditis during therapy, bacteremia during therapy, abscess and cellulitis, presumed infectious arthritis, renal transplantation during rejection, collagen disease, sarcoidosis, lymphoma, and colitis. Isolates in hypertonic media were reverted to parent form by agar passage. In only 5% of these selected cases were organisms found in hypertonic, but not conventional, media that appeared on the basis of repeated isolation and/or serological studies to come from the patient. Nine of the 16 appeared to be of major significance. The two groups in which use of highly enriched, hypertonic media seemed most helpful were suspected endocarditis and undefined meningitis with negative cultures using standard media. The most effective of the hypertonic media used was 0.3 M sucrose in brain heart infusion with 20% horse serum. In most instances, the organism grew only in the hypertonic sucrose, and in most cases it appeared in conventional rather than aberrant form. Hypertonic media, especially 0.3 M sucrose, are of substantial helpin a small number of carefully selected cases.     

Sequence comparison of the ARG4 chromosomal regions from the two related yeasts, Saccharomyces cerevisiae and Saccharomyces douglasii

A 3.6 kb DNA fragment from Saccharomyces douglasii, containing the ARG4 gene, has been cloned, sequenced and compared to the corresponding region from Saccharomyces cerevisiae. The organization of this region is identical in both yeasts. It contains besides the ARG4 gene, another complete open reading frame (ORF) (YSD83) and a third incomplete one (DED81). The ARG4 and the YSD83 coding regions differ from their S. cerevisiae homologs by 8.1% and 12.5%, respectively, of base substitutions. The encoded proteins have evolved differently: amino acid replacements are significantly less frequent in Arg4 (2.8%) than in Ysc83 (12.4%) and most of the changes in Arg4 are conservative, which is not the case for Ysc83. The non-coding regions are less conserved, with small AT-rich insertions/deletions and 20% base substitutions. However, the level of divergence is smaller in the aligned sequences of these regions than in silent sites of the ORFs, probably revealing a higher degree of constraints. The Gcn4 binding site and the region where meiotic double-strand breaks occur, are fully conserved. The data confirm that these two yeasts are evolutionarily closely related and that comparisons of their sequences might reveal conserved protein and DNA domains not expected to be found in sequence comparisons between more diverged organisms.     

Review: the Cct eukaryotic chaperonin subunits of Saccharomyces cerevisiae and other yeasts

All eight of the CCT1-CCT8 genes encoding the subunits of the Cct chaperonin complex in Saccharomyces cerevisiae have been identified, including three that were uncovered by the systematic sequencing of the yeast genome. Although most of the properties of the eukaryotic Cct chaperonin have been elucidated with mammalian systems in vitro, studies with S. cerevisiae conditional mutants revealed that Cct is required for assembly of microtubules and actin in vivo. Cct subunits from the other yeasts, Candida albicans and Schizosaccharomyces pombe, also have been identified from partial and complete DNA sequencing of genes. Cct8p from C. albicans, the only other completely sequenced Cct protein from a fungal species other than S. cerevisiae, is 72% and 61% similar to the S. cerevisiae and mouse Cct8 proteins, respectively.     

Factors which affect the frequency of sporulation and tetrad formation in Saccharomyces cerevisiae baker's yeasts

To clarify the role that respiration, the mitochondrial genome, and interactions of mitochondria and nucleus play on sporulation and to improve the sporogenic ability of several baker's yeasts, an investigation of the effects of different media and culture conditions on baker's yeast sporulation was undertaken. When standard protocols were followed, the sporulation frequency varied between 20 and 60% and the frequency of four-spore asci varied between 1 and 6%. Different presporulation and sporulation media, the use of solid versus liquid media, and incubation at 22 versus 30 degrees C were checked, and the cells were collected from presporulation media in either exponential or stationary phase. Best results, yielding sporulation and four-spore ascus formation frequencies up to 97 and 60%, respectively, were obtained by collection of the cells in exponential phase from liquid presporulation medium with 10% glucose and transfer of them to sporulation medium with 0.5% potassium acetate at 22 degrees C. Under these conditions, the most important factor was the growth phase (exponential versus stationary) at which cells from presporulation medium were collected. Changes in sporulation frequencies were also measured after transfer of mitochondria from different sources to baker's yeasts. When mitochondria from laboratory, baker's, and wine yeasts were transferred to baker's and laboratory petite strains, sporulation and four-spore ascus formation frequencies dropped dramatically either to no sporulation at all or to less than 50% in both parameters. This transfer also resulted in an increase in the frequency of petite mutant formation but yielded similar growth and respiration rates in glycerol.(ABSTRACT TRUNCATED AT 250 WORDS)     

The possible carcinogenic action of a protein concentrate from Saccharomyces yeasts grown on molasses

A testing was done in a chronic experiment on 300 rats and 360 mice of both sexes for carcinogenic potential of a new protein product from Saccharomyces yeast grown in melasse. The production procedures and techniques of the above product have been worked out at the Ukrainian Research Institute of Spirits and Biotechnology of Food Stuffs of Gospishcheprom (State Food Industry) of Ukraine. The studies made showed the new protein product has no carcinogenic effect.     

Growth of yeasts in milk and associated changes to milk composition

The growth of several yeast species in milk containing added sodium chloride (0-15%, w/v) at 25 degrees C and 10 degrees C was examined in conjunction with yeast metabolism of milk constituents. Depending on conditions, all yeasts grew to maximum populations of 10(7)-10(8) cfu/ml. Kluyveromyces marxianus gave strong utilisation of lactose and weak metabolism of citrate, protein and fat with the production of ethanol, glycerol, lactic acid and propionic acid. As measured by the production of free amino acids and free fatty acids, Candida lipolytica and Candida catenulata gave strong proteolytic and lipolytic reactions, the specificities of which appeared to be influenced by temperature and the presence of NaCl. These species also metabolised organic acids. Although giving strong growth responses, Debaryomyces hansenii and Saccharomyces cerevisiae did not metabolise lactose and gave only very weak lipolytic and proteolytic reactions. Citrate was metabolised by D. hansenii but not by S. cerevisiae. Both species produced small amounts of ethanol, glycerol and lactic acid.     

Effect of growth temperature and culture age on the lipid composition of Vibrio cholerae 569B (Inaba)

The relative amounts of the major phospholipids (phosphatidylethanolamine, phosphatidylglycerol and lyso-phosphatidylethanolamine) and fatty acids in Vibrio cholerae 569B (Inaba) varied with growth temperature and between exponential and stationary phases of growth.     

Autonomous metabolic oscillation in continuous culture of Saccharomyces cerevisiae grown on ethanol

The electrophoretic profiles of outer membrane proteins and lipopolysaccharide of sixty-five enterotoxigenic Escherichia coli of different serotypes and virulence-associated factors, toxin and colonization factors were determined. A close relationship between serotype and outer membrane protein and lipopolysaccharide patterns could be observed. No correlation could be found between the electrophoretic profiles and the expression of virulence-associated factors. The observed homogeneity of outer membrane protein and lipopolysaccharide profiles suggested the presence of only a few clones in the samples studied, and supported the use of outer membrane protein and lipopolysaccharide analysis as a useful epidemiological tool in the characterization of enterotoxigenic Escherichia coli isolates.     

Influence of lead on metabolism of vitamins B group in alimentary iron deficient rats

Gamma delta T-Cells represent a minor subpopulation of T-lymphocytes in man and their role in normal and diseased human skin is unknown. This article is a comprehensive review of T-lymphocytes bearing the gamma delta T-cell receptor in normal and pathological human skin. Firstly, we have documented the occurrence of gamma delta T-cells in normal skin and in a range of reactive and malignant skin conditions. We have then discussed the experimental findings regarding the repertoire used by gamma delta T-cells in normal human skin and in cutaneous disorders with an increased percentage of gamma delta T-cells.     

The growth of Rhodotorula rubra yeasts and their synthesis of ergosterol on media with lovastatin

The effect of lovastatin, a competing inhibitor of 3-hydroxy-3-methylglutaryl-CoA-reductase (HMG-CoA-reductase) of the fungal origin on the growth of and ergosterol biosynthesis by Rh. rubra VKPM Y 1337 was studied. It was shown that the yeast growth was inhibited by lovastatin in concentrations of 0.25 to 5.0 micrograms/ml when the inhibitor was added to the cultivation medium either with the inoculum or at later periods of the yeast cultivation. In concentrations of 2.0 to 5.0 micrograms/ml lovastatin almost completely inhibited the yeast growth. In the concentrations tested the inhibitor did not decrease the ergosterol level in the yeast cells below 40 per cent of the control. When lovastatin was added in concentrations of 1.0 to 5.0 micrograms/ml the maximum inhibition of the ergosterol biosynthesis was observed at the end of the growth log phase. Further cultivation of the yeast in the presence of the inhibitor resulted in an increase of the ergosterol biosynthesis. It is believed that the increase in the quantity of ergosterol may be due either to the HMG-CoA-reductase induction under the action of the inhibitor or to its inactivation as a result of the hydroxylation.     

A formal system of approval for monographs in the pharmacopoeia of culture media--statement from the IUMS-ICFMH working party on culture media

By site-directed mutagenesis on human cytidine deaminase (CDA), five mutant proteins were obtained: C65A, C99A, C102A, E67D and E67Q. The three cysteine mutants were completely inactive, whereas E67D and E67Q showed a specific activity about 200- and 200000-fold lower, respectively, than the wild-type CDA. Zinc analysis revealed that only E67D, E67Q and C65A contained 1 mol Zn2+/mol subunit as in the wild-type CDA. Kinetic measurements with the specific carboxylic group reagent N-ethoxy-carbonyl-2-ethoxy-1,2-dihydroquinoline performed on wild-type CDA suggest that Glu67 is essential for the catalytic process. Furthermore, when both native and denatured CDA was titrated with 5,5'-dithiobis(2-nitrobenzoic acid) six sulfhydryl groups were detected, whereas in the denatured and reduced enzyme nine such groups were found, according to the sequence data. When p-hydroxymercuriphenyl sulfonate was used, nine sulfhydryl groups were detectable and the release of 1 mol of zinc per mole of CDA subunit was revealed by the metal indicator dye 4-(2-pyridylazo)resorcinol. It seems plausible that the limiting step for the maintenance of zinc in the active site is the formation of coordination between Cys99 and Cys102, whereas Cys65 could lead the zinc to the correct position and orientation within the active site.     

Effect of a Saccharomyces cerevisiae culture on nutrient digestion in lactating dairy cows

The digestive effects of a Saccharomyces cerevisiae culture were investigated. Four cows in early lactation that were fitted with ruminal and duodenal cannulas were used in a crossover design. The diet, which consisted of 60% corn silage and 40% concentrates, was supplemented or not supplemented with a daily dose of 50 g of premix containing 0.5 g of S. cerevisiae (6 x 10(8) cfu/g of premix). Total and ruminal digestibilities of organic matter, duodenal flows of nonmicrobial and microbial N, solid and liquid turnover rates, ruminal protozoal numbers, pH, ammonia N and volatile fatty acid concentrations, and concentrations of some plasma metabolites were not modified by the addition of S. cerevisiae. Ruminal dry matter content increased when S. cerevisiae was supplemented to the diet. In situ ruminal degradabilities of dry matter and neutral detergent fiber from corn stalk and of N from soybean meal were not modified; degradability of acid detergent fiber from corn stalk increased (32.5% vs. 26.3%) with the addition of S. cerevisiae. A short-term increase in N degradation was observed after 4 and 8 h of incubation. This experiment showed no effect of S. cerevisiae on most quantitative digestive events; however, a positive transitory postprandial effect on some parameters of microbial activity was observed.     

Effect of milling in various media on the composition and some properties of niobium carbide

Conclusions Comminution of carbides in various media which do not prevent the well-developed surfaces of their particles from coming into contact with water and oxygen leads to surface oxidation of these particles. This is reflected in the chemical composition of carbides, which almost continually changes during sintering in the usual temperature range, right up to 2200C, and in the densification kinetics and properties of carbide-base materials. Because of the instability of oxycarbides of the Group V metals in a vacuum at these temperatures, with the carbides Me^vC (NbC and TaC) the surface oxidation experienced by their particles during milling in certain dispersing media may have an activating effect on the sintering process and shift the composition of the carbides toward the lower limits of their homogeneity ranges.Translated from Poroshkovaya Metallurgiya, No. 2(170), pp. 23–28, February, 1977.     

Recombinant protein production via fed-batch culture of the yeast Saccharomyces cerevisiae

Protein production with the recombinant yeast Saccharomyces cerevisiae in fed-batch culture is investigated in this work using beta-galactosidase as a model protein. Segregational instability was negligible during the observed culture periods. The final volumetric productivity, as determined by both cell concentration and gene expression, was strongly affected by the time course of the glucose levels in the bioreactor. It was found that an average glucose feed rate of 1.31 g glucose h-1 resulted in both the maximum beta-galactosidase production rate of 831-950 units ml-1 h-1 and the maximum cell production rate of 0.520-0.524 mg ml-1 h-1.     

Twenty-four hour heart rate variability in patients with acute myocardial infarction depending on treatment]

Heart rate variability is a useful prognostic parameter in patients with coronary artery disease. SDNN (standard deviation of all normal RR intervals in the entire ECG 24 hour recording) was evaluated in patients with acute myocardial infarction (AMI), who were divided in two groups: The first group consisted of 22 patients who had not received streptokinase; in the second group there were 10 patients, who were treated with streptokinase and in whom indirect reperfusion criteria were observed. Two control groups were drawn into the study: the third included 30 patients with stable ischaemic heart disease with no history of myocardial infarction and the fourth group of 18 healthy subjects. SDNN was calculated by the ECG Mediarc Premier II Holter System (DRG International Inc., NJ, USA) in the time domain from 24 hour ECG recordings. Mean SDNN divided by standard deviation values were: I: 88.1 divided by 25.1 ms; II: 96.7 divided by 24.3 ms; III: 107.5 divided by 22.6 ms; IV: 136.0 divided by 20.4 ms. No significant difference in SDNN was found between heart infarct patients, who were and were not thrombolyzed (96.7 divided by 24.3 ms vs. 88.1 divided by 25.6 ms; p > 0.05) as well as between thrombolyzed infarct patients and patients with stable ischaemic heart disease with no history of myocardial infarction (96.7 divided by 24.3 ms vs. 107.5 divided by 22.6 ms; p > 0.05). However, a significant difference in SDNN was observed between patients who had not been thrombolyzed and patients with stable ischaemic heart disease (88.1 divided by 25.6 ms vs. 107.5 divided by 22.6 ms; p < 0.01).     

Changes in vacuolar protease activities during synchronous culture of Saccharomyces cerevisiae

Enzymatic activities of proteinases A and B, carboxypeptidase Y, and aminopeptidase I, vacuolar enzymes in beer yeast, Saccharomyces cerevisiae, were measured at different stages of growth in the synchronous culture. All enzymatic activities fluctuated synchronously during the cell growth in a periodical cycle. The maximum activities were observed before cytokinesis and the minimum activities were found just after completing cytokinesis.