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Mol Gen Genet, 1977 Jul 20, 154(2), 181 - 4 Cytoplasmic and mitochondrial protein synthesis in the "petite-negative" yeast Kluyveromyces lactis . Cytoplasmic inheritance of resistance to tetracycline; Guerrini AM et al.; The growth of two strains of the "petite-negative" yeast Kluyveromyces lactis is inhibited by Tetracycline in different ways under the same culture conditions . Tetracycline resistant mutants of one strain have been isolated which can tolerate doses as high as 3000 microgram/ml of antibiotic . The segregation pattern of this character obtained by random spore analysis of the ascospores derived from the cross of the two strains strongly suggests that the resistance to tetracycline is under mitochondrial control. Mol Gen Genet, 1977 Apr 29, 152(3), 325 - 9 Chromosomal and extrachromosomal inheritance of erythromycin-resistance in the "petite-negative" yeast Kluyveromyces lactis; Del Giudice L et al.; Spontaneously arising erythromycin-resistant mutants were isolated in the "petite-negative" yeast Kluyveromyces lactis . Two independently arising mutants were studied, in one erythromycin-resistance was conferred by a single dominant nuclear gene, and in the other the resistance was extrachromosomally inherited . In fermentable medium growth of sensitive and resistant strains in presence or absence of erythromycin does not qualitatively change the cytochrome absorption spectra, whereas oxygen uptake of parental strains growing in glucose-medium is affected by the drug . The importance of "petite-negative" yeasts like Kluyveromyces lactis for the study of nucleo-cytoplasmic interrelations is discussed. Mol Gen Genet, 1977 Apr 29, 152(3), 183 - 91 The isolation and genetic characterization of extrachromosomal chloramphenicol and oligomycin-resistant mutants from the petite-negative yeast Kluyveromyces lactis; Brunner A et al.; Spontaneous mutants of the petite-negative yeast Kluyveromyces lactis, resistant to the antibiotics chloramphenicol and oligomycin, were isolated and genetically characterized . Three chloramphenicol-resistant mutants showed non-Mendelian inheritance when crossed to sensitive parents . Of 5 oligomycin-resistant strains studied, three exhibited resistance due to the presence of an extrachromosomal mutation . The resistance of the other two deriving from a nuclear and recessive mutation . When two factor crosses in trans configuration were performed between two of the chloramphenicol and the five oligomycin-resistant mutants a polarity in recombination was observed with a predominance of sensitive (OSCS) over resistant (ORCR) reciprocal recombinants . Allelism tests carried out among the oligomycin-resistant mutants indicated the presence of at least two distinct extrachromosomal regions responsible for the resistance. Biotechnol Bioeng, 1977 Mar, 19(3), 387 - 97 The immobilization of microbial cells, subcellular organelles, and enzymes in calcium alginate gels; Kierstan M et al.; Saccharomyces cerevisiae cells, Kluyveromyces marxianus cells, inulase, glucose oxidase, chloroplasts, and mitochondria were immobilized in calcium alginate gels . Ethanol production from glucose solutions by an immobilized preparation of S . cerevisiae was deomonstrated over a total of twenty-three days, and the half-life of such a preparation was shown to be about ten days . Immobilized K . marxianus, inulase, and glucose oxidase preparations were used to demonstrate the porosity and retraining properties of calcium alginate gels . Calcium alginate-immobilized chloroplasts were shown to perform the Hill reaction . Some experiments with immobilized mitochondria are reported. Mol Gen Genet, 1977 Jan 18, 150(2), 137 - 40 Dependence of cytoplasmic on mitochondrial protein synthesis in K . Lactis CBS 2360 . I . Biochemical analysis; Zennaro E et al.; In the "petite negative" yeast Kluyveromyces lactis (strain CBS 2360) growth is inhibited by the same Erythromycin concentrations on fermentable and non-fermentable carbon sources . The minimal inhibitory concentrations of Erythromycin does not affect respiration, but completely inhibits total aminoacid incorporation by the cells in conditions in which permeability effects can be ruled out . The effect of the antibiotic on the "in vitro" protein synthesis by cytoplasmic and mitochondrial systems shows that inhibition is effective only at the mitochondrial level . Results suggest that the inhibition of growth and of total protein synthesis is a consequence of the inhibition of mitochondrial protein synthesis. C R Seances Soc Biol Fil, 1977, 171(5), 1029 - 33 {The effect of dissolved oxygen tension on the energy metabolism of yeasts}; Peringer P; The specific ATP generation rate in yeasts was examined on the glycolytic pathway and on the respiratory chain as a function of the dissolved oxygen tension of the culture medium . Two different strains were used: Saccharomyces cerevisiae sensitive to the glucose effect and Kluyveromyces fragilis insensitive to the catabolite respression when growing on lactose . The oxidative ATP generation rate followed by these two strains a Michaelis Menten kinetics against the dissolved oxygen concentration . Dissolved oxygen tension only influenced the glycolytic ATP generation rate in Kluyveromyces fragilis . Thus glucose and Pasteur effects are two mutually exclusive regulatory mechanisms of the energy yielding metabolism of the yeasts. Appl Environ Microbiol, 1977 Jan, 33(1), 137 - 46 Hydrolysis of lactose by immobilized microorganisms; Ohmiya K et al.; Cells of Lactobacillus bulgaricus, Escherichia coli, and Kluyveromyces (Saccharomyces) lactis immobilized in polyacrylamide gel beads retained 27 to 61% of the beta-galactosidase activity of intact cells . Optimum temperature and pH and thermostability of these microbial beta-galactosidases were negligibly affected by the immobilization . Km values of beta-galactosidase in immobilized cells of L . bulgaricus, E . coli, and K . lactis toward lactose were 4.2, 5.4, and 30 mM, respectively . Neither inhibition nor activation of beta-galactosidase in immobilized L . bulgaricus and E . coli appeared in the presence of galactose, but remarkable inhibition by galactose was detected in the case of the enzyme of immobilized K . lactis . Glucose inhibited noncompetitively the activity of three species of immobilized microbial cells . These kinetic properties were almost the same as those of free beta-galactosidase extracted from individual microorganisms . The activity of immobilized K . lactis was fairly stable during repeated runs, but those of E . coli and L . bulgaricus decreased gradually . These immobilized microbial cells, when introduced into skim milk, demonstrated high activity for converting lactose to monosaccharides . The flavor of skim milk was hardly affected by treatment with these immobilized cells, although the degree of sweetness was raised considerably. Arch Microbiol, 1976 Aug, 109(1-2), 153 - 6 {Kluyveromyces blattae sp . n., a new multispored yeast for Blatta orientalis (author's transl)}; Henninger W et al.; A new hitherto undescribed species of yeast of the genus Kluyveromyces has been isolated for the intestinal tract of the oriental cockroach (Blatta orientalis) . A description of the new species including latin diagnosis is given. Biochim Biophys Acta, 1976 Mar 5, 426(2), 302 - 16 Evidence for an inducible glucose transport system in Kluyveromyces lactis; Royt PW et al.; To find the cause of delayed glucose oxidation in succinate-grown Kluyveromyces lactis, glucose transport was studied in glucose- and in succinate-grown cells . The initial rate of 2-deoxyglucose (2-dGlc) accumulation, as well as the appearance of 2-deoxyglucose 6-phosphate, was higher in the glucose-grown cells . In both cell types, 2-dGlc was apparently transported in the free form to be phosphorylated intracellularly . In glucose-grown cells the level of free 2-dGlc in the pool was always less than the external concentration . Exchange transport in starved, poisoned cells loaded with unlabeled 2-dGlc was 140-fold greater in glucose- than in succinate-grown cells, probably beacuse of the presence of an inducible transport component . The development of the increased rate of transport in a succinate-grown uracil-requiring auxotroph after transfer to glucose depends on the presence of uracil. Rev Farm Bioquim Univ Sao Paulo, 1976 Jan-Jun, 14(1), 55 - 68 {Whey as a substrate for obtaining an edible yeast}; Terra NN; Using a fermentative process of whey through Kluyveromyces fragilys, Jorgensen, the Author prepared two edible products: Biomass I (yeast) and Biomass II (yeast plus protein of whey) . Biomass I offered 53% of protein, and the yield was 22,3 g/1 whey . Biomass II, 62% of protein and yield of 27,7 g/1 whey . The test of food efficiency for Biomass II was similar to that presented by casein; the protein eficiency ratio at the level of 5% was the same, both for Biomass I and II . More research is needed specially to determine the economical convenience of the process. Z Allg Mikrobiol, 1976, 16(7), 529 - 36 {Alcohol dehydrogenase (ADH) in yeast cells . I . Cytoplasmic, mitochondrial and nuclear ADH in Saccharomyces carlsbergensis and Kluyveromyces fragilis}; Kunkel W et al.; When grown in a medium containing lactat, Saccharomyces carlsbergensis produces 5 times more ground-plasmatic ADH than Kluyveromyces fragilis . Upon gelectrophoresis, K . fragilis exhibits 7 bands while S . carlsbergensis shows only one . In a polyacrylamid gradient, the ADH's of both strains yield one band, the position of which corresponds to a molecular weight of about 160 000 D . In cell homogenates and mitochondrial fractions of S . carlsbergensis treated with ultrasound, an ADH is detected which exhibits 3 subbands and a molecular weight greater than 1 Megadalton . This ADH does not occur in K . fragilis . Mitochondrial fractions from K . fragilis contain an ADH, the electrophoretical mobility of which is identical to that of the ADH of the groundplasma . Nuclei of S . carlsbergensis also possess ADH whereas those of K . fragilis probably do not. Z Allg Mikrobiol, 1976, 19(5), 361 - 7 Histone-like protein fractions of Kluyveromyces fragilis and their relation to the cell cycle; Penman CS et al.; Protein fractions were obtained from Kluyveromyces fragilis by pH titration, a technique used for histone extraction, following the inclusion of a distilled water extraction stage, and the fractions partially characterized . The inclusion of a distilled water step resulted in a tenfold purification of the fraction obtained at pH 2.20 as compared with pH titration alone . In synchronous cultures induced with 2'-deoxyadenosine or prepared by selection this fraction displayed a stepwise accumulation, and doubled in quantity at a point about one third of a cycle after cell division . The fraction obtained at pH 1.35 resembled calf thymus f2a2 histone in its extraction properties and amino acid composition, and also showed a possible stepwise accumulation . Other fractions appear to accumulate exponentially. Mycopathologia, 1975 Dec 23, 57(2), 79 - 88 A critical study of the taxonomic value of some tests of assimilation used for the classification of the sporogenous yeasts; Fiol JB; Six texts of assimilation used in the taxonomy of yeasts, (lactose, maltose, cellobiose, trehalose, melibiose, sucrose) have been critically tested by the examination of intracellular enzymic systems . The results obtained among the sporogenous species of Saccharomyces, Kluyveromyces, Pichia, Hansenula, Debaryomyces indicate that cellobiose, lactose, maltose and trehalose tests no longer supply an important value for the speciation, because the number of cryptical osidases is so high. J Dairy Sci, 1975 Nov, 58(11), 1620 - 9 Selection of strain, growth conditions, and extraction procedures for optimum production of lactase from Kluyveromyces fragilis; Mahoney RR et al.; Forty-one strains of Kluyveromyces fragilis (Jorgensen) van der Walt 1909 varied 60-fold in ability to produce lactase (beta-galactosidase) . The four best strains were UCD No . 55-31 (Northern Regional Research Center NRRL Y-1196), UCD No . C21(-), UCD No . 72-297(-), and UCD No . 55-61 (NRRL Y-1109) . Biosynthesis of lactase during the growth of K . fragilis strain UCD No . 55-61 was followed on both lactose and sweet whey media . Maximum enzyme yield was obtained at the beginning of the stationary phase of growth . Bets lactase yields from K . fragilis UCD No . 55-61 were obtained with 15% lactose and an aeration rate of at least .2 mmol oxygen/liter per min . Supplementary growth factors were unneccessary for good lactase yeilds when yeast was grown on whey media . Best extraction of lactase from fresh yeast cells was obtained by toluene autolysis (2% vol/vol) at 37 C in .1 M potassium phosphate buffer, pH 7.0, containing .1 mM manganese chloride and .5 mM magnesium sulfate . The enzyme was concentrated and purified partially by acetone precipitation . At least 95% of the enzyme activity of the concentrated solution was retained after storage for 7 days at 22 C, for 3 wk at 4 C, and for 6 wk at -20 C. J Gen Microbiol, 1975 Sep, 90(1), 76 - 80 2'-Deoxyadenosine and A23187 as agents for inducing synchrony in the budding yeast, Kluyveromyces fragilis; Penman CS et al.; The effects of induction synchrony by 2'-deoxyadenosine and the ionophore A23187 were compared with selection synchrony methods in Kluyveromyces fragilis . 2'-Deoxyadenosine synchronizes nuclear division and this is followed by synchronous cell division, but DNA synthesis is not synchronized . The ionophore A23187 also induces synchronous nuclear division and synchronous cell division, but likewise does not synchronize DNA synthesis. J Biol Chem, 1975 May 10, 250(9), 3426 - 35 Biosynthesis of yeast mannan . Isolation of Kluyveromyces lactis mannan mutants and a study of the incorporation of N-acetyl-D-glucosamine into the polysaccharide side chains; Smith WL et al.; One side chain in the cell wall mannan of the yeast Kluyveromyces lactis has the structure (see article) . (Raschke, W . C., and Ballou, C . E . (1972) Biochemistry 11, 3807) . This (Man)4GNAc unit (the N-acetyl-D-glucosamine derivative of mannotetroase) and the (Man)4 side chain, aMan(1 yields 3)aMan(1 yields 2)aMan(1 yields 2)Man, are the principle immunochemical determinants on the cell surface . Two classes of mutants were obtained which lack the N-acetyl-D-glucosamine-containing determinant . The mannan of one class, designated mmnl, lacks both the (Man)4GNAc and (Man)4 side chains . Apparently, it has a defective alpha-1 yields 3-mannosyltransferase and the (Man)4 unit must be formed to serve as the acceptor before the alpha-1 yields 2-N-acetyl-glucosamine transferase can act . The other mutant class, mnn2, lacks only the (Man)4GNAc determinant and must be defective in adding N-acetylglucosamine to the mannotetrasose side chains . Two members of this class were obtained, one which still showed a wild type N-acetylglucosamine transferase activity in cell-free extracts and the other lacking it . They are allelic or tightly linked, and were designated mnn2-1 mnn2-2 . Protoplast particles from the wild type cells catalyzed a Mn2+-dependent transfer of N-acetylglucosamine from UDP-N-acetylglucosamine to the mannotetraose side chain of endogenous acceptors . Exogenous mannotetraose also served as an acceptor in a Mn2+-dependent reaction and yielded (Man)4GNAc . Related oligosaccharides with terminal alpha (1 yields 3)mannosyl units were also good acceptors . The product from the reaction with alphaMan(1 yields 3)Man had the N-acetylglucosamine attached to the mannose unit at the reducing end, which supports the conclusion that the cell-free glycosyltransferase activity is identical with that involved in mannan synthesis . The reaction was inhibited by uridine diphosphate . Protoplast particles from the mmnl mutants showed wild type N-acetylglucosamine transferase activity with exogenous acceptor, but they had no endogenous activity because the endogenous mannan lacked acceptor side chains . Particles from the mnn2-1 mutant failed to catalyze N-acetylglucosamine transfer . In contrast, particles from the mnn2-2 mutant were indistinguishable from wild type cells in their transferase activity . Some event accompanying cell breakage and assay of the mnn2-2 mutant allowed expression of a latent alpha-1 yields 2-N-acetylglucosamine transferase with kinetic properties similar to those of the wild type enzyme. Can J Microbiol, 1975 Apr, 21(4), 473 - 80 Dual effects of glucose on dicarboxylic acid transport in Kluyveromyces lactis; Zmijewski MJ Jr et al.; The properties of succinate uptake in succinate-grown Kluyveromyces cells were examined . The rate of succinate transport at 15C exhibits an approximate V-max of 1.2 mumol times h-1 times mg-1 dry weight of cells and an apparent K-m of 18 muM . The uptake process appears to be tightly coupled to metabolism . L-Malate, fumarate, and alpha-ketoglutarate were the only other dicarboxylates tested, which were found to inhibit succinate transport . The aggreement between the order of inhibition of succinate transport by these dicarboxylates and their rates of uptake, as well as the competitive nature of the inhibition are all consistent with the existence of a common carrier system showing specificity for dicarboxylates of the TCA cycle . Cells transferred from succinate to glucose medium rapidly lose their ability to transport succinate . Glucose-grown cells also exhibit an inability to oxidize dicarboxylates or to use them for growth without a very long lag . The dicarboxylate uptake system, therefore, appears to be subject to a strong catabolite repression . The depression of the succinate transport system requires the presence of succinate, as well as low concentrations of glucose. Nucleic Acids Res, 1975 Feb, 2(2), 239 - 55 In vivo and in vitro effects of rifampicin and streptolydigin on transcription of Kluyveromyces lactis in the presence of nystatin; Plevani P et al.; Rifampicin and streptolydigin, if used in conjunction with nystatin, depress the growth of Kluyveromyces lactis . The incorporation of labeled leucine into protein is inhibited by nystatin whereas the incorporation of labeled uracil into RNA is inhibited by rifampicin in nystatin-treated cells . In order to study the mechanism of inhibition of RNA synthesis we purified by DEAE-Sephadex column chromatography four forms of RNA polymerase from K.lactis cells . The general properties of these enyzmes are similar to those of Saccharomyces cerevisiae and of other eukaryotic RNA polymerases . In particular, enzymes IA, IB and III are more active with poly{d(A-T)} template and Mn-2+ than with native or denatured calf thymus DNA . Enzyme II shows optimal activity with denatured calf thymus DNA and Mn2+ . When challenged with native calf thymus DNA all enzymes prefer Mg-2+ as a divalent cation whereas with denatured calf thymus DNA all enzymes are more active with Mn-2+ . Enzyme II is inhibited by lambda-amanitin but no enzyme is sensitive to rifampicin and streptolydigin . The inhibition of growth and uracil uptake observed when rifampicin is added to nystatin treated cells is probably not caused by a specific inhibition of transcription. Antonie Van Leeuwenhoek, 1975, 41(1), 81 - 8 DNA base composition of species of the genus Saccharomyces; Yarrow D et al.; DNA base compositions (GC content) of Saccharomyces species are reported and discussed . Several amendments of the four groups given by van der Walt are suggested, viz . the transfer of S . kluyveri to group 1, and of S . eupagycus, S . cidri, S . montanus, S . microellipsodes and S . florentinus to group 2 . The synonomy of S . amurcae and S . cidri is suggested . The DNA base compositions revealed two possible pairs of sibling species: S . elegans and S . bailii, with a difference in GC content of 4.1%; S . dairensis and S . servazzii with a difference in GC content of ca . 3% . S . mrakii had a GC content of 47.3-48.5% the highest encountered in this genus and similar to that of Kluyveromyces thermotolerans. Pathol Microbiol (Basel), 1975, 42(1), 49 - 58 Antigenic relationships between Candida albicans and various yeasts as reflected by immunoglobulin-class specificity; Segal E et al.; A group of guinea pigs was inoculated into the foot pads with a single dose of Candida albicans in complete Freund's adjuvant, while another group was similarly inoculated once in the foot pads but also several times intramuscularly, with Candida alone . All guinea pigs were bled at different intervals after immunization and sera were separated chromatographically into IgG and IgM fractions . In order to study the antigenic relationships as reflected by immunoglobulin-class specificity, IgG and IgM fractions and whole sera obtained from guinea pigs differently immunized, were tested for the presence of agglutinins against C . albicans, six other species of Candida, and species of the ascosporogenous genera Saccharomyces, Kluyveromyces and Schizosaccharomyces . The results show that (1) only IgG fractions of the different sera prepared contained the specific anti-C . albicans antibodies; (2) IgG and IgM fractions of the sera obtained from a single inoculation did not reveal a specific pattern expressing antigenic relationships of the yeast studied, and (3) the IgM fractions of the sera obtained from several inoculations had a more homogenous pattern of reactivity, since mainly these contained the agglutinins against the ascosporogenous yeast species.
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