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1.
Brzezińska-Rodak M Zymańczyk-Duda E Klimek-Ochab M Kafarski P Lejczak B 《Biotechnology letters》2006,28(7):511-513
Both R- and S-phenylethyl alcohol of high enantiomeric purity (98%) and with a satisfactory yield (40–80%) were obtained by bioreduction
of acetophenone, catalyzed by whole cells of baker’s yeast.
Revisions requested 29 November 2005; Revisions received 9 January 2006 相似文献
2.
Dorta C Cruz R de Oliva-Neto P Moura DJ 《Journal of industrial microbiology & biotechnology》2006,33(12):1003-1009
Different concentrations of sucrose (3–25% w/v) and peptone (2–5% w/v) were studied in the formulation of media during the cultivation of Aspergillus japonicus-FCL 119T and Aspergillus niger ATCC 20611. Moreover, cane molasses (3.5–17.5% w/v total sugar) and yeast powder (1.5–5% w/v) were used as alternative nutrients for both strains’ cultivation. These media were formulated for analysis of cellular growth, β-Fructosyltransferase and Fructooligosaccharides (FOS) production. Transfructosylating activity (U
t
) and FOS production were analyzed by HPLC. The highest enzyme production by both the strains was 3% (w/v) sucrose and 3% (w/v) peptone, or 3.5% (w/v) total sugars present in cane molasses and 1.5% (w/v) yeast powder. Cane molasses and yeast powder were as good as sucrose and peptone in the enzyme and FOS (around 60% w/w) production by studied strains. 相似文献
3.
Olianas A Manconi B Masia D Sanna MT Castagnola M Salvadori S Messana I Giardina B Pellegrini M 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2009,179(2):193-203
Arthropod hemocyanins transport and store oxygen and are composed of six subunits, or multiples thereof depending on the species.
Palinurus gilchristi hemocyanin is found only as 1 × 6-mers, as normally occurs in spiny lobsters. An alkaline pH and removal of calcium ions
induce a wholly reversible dissociation into monomers. The oxygen-binding properties of 1 × 6-meric hemocyanin from P. gilchristi were investigated with respect to pH and modulating effect exerted by calcium, lactate and urate. The oxygen affinity was
highly affected by pH in the presence of calcium ions, while in its absence the Bohr coefficient became 60% lower. The protein
is insensitive to lactate, but affected by urate which markedly increased hemocyanin–oxygen affinity, acting as the physiological
major positive effector. Calcium ions decrease oxygen affinity at low concentration range (0–1 mM), while as concentration
becomes higher than 100 mM, the oxygen affinity increases, indicating the presence of two independent types of calcium-binding
sites with high and low affinity, respectively. The previous hypothesis, that the presence of high-affinity binding sites
in addition to low affinity ones could be a characteristic feature of Palinuran hemocyanins, has been tested by analyzing,
with respect to calcium–hemocyanin interaction, three other species belonging to Palinura. 相似文献
4.
The cloning of α-amylase gene ofS. occidentalis and the construction of starch digestible strain of yeast,S. cerevisiae AS. 2. 1364 with ethanol-tolerance and without auxotrophic markers used in fermentation industry were studied. The yeast/E.coli shuttle plasmid YCEp1 partial library ofS. occidentalis DNA was constructed and α-amylase gene was screened in S.cerevisiae by amylolytic activity. Several transformants with amylolysis were obtained and one of the fusion plasmids had an about 5.0
kb inserted DNA fragment, containing the upstream and downstream sequences of α-amylase gene fromS. occidentalis. It was further confirmed by PCR and sequence determination that this 5.0 kb DNA fragment contains the whole coding sequence
of α-amylase. The amylolytic test showed that when this transformant was incubated on plate of YPDS medium containing 1 %
glum and 1 % starch at 30°C for 48 h starch degradation zones could be visualized by staining with iodine vapour. α-amylase
activity of the culture filtratate is 740–780 mU/mL and PAGE shows that the yeast harboring fusion plasmids efficiently secreted
α-amylase into the medium, and the amount of the recombinant α-amylase is more than 12% of the total proteins in the culture
filtrate. These results showed that α-amylase gene can be highly expressed and efficiently secreted inS. cerevisiae AS. 2.1364, and the promotor and the terminator of α-amylase gene fromS. occidentalis work well inS. cercvisiac AS. 2.1364. 相似文献
5.
The objective of this study was to compare the efficacy of eight Blastomyces dermatitidis yeast phase lysate antigens (T-58: dog, Tennessee; T-27: polar bear, Tennessee; ERC-2: dog, Wisconsin; B5894: human, Minnesota;
SOIL: soil, Canada; B5896: human, Minnesota; 48089: human, Zaire; 48938: bat, India) in the detection of the immunoglobulins
IgG and IgM in serum specimens from canines with blastomycosis. An indirect enzyme-linked immunosorbent assay (ELISA, peroxidase
system) was used to analyze sera collected during four different intervals post-infection. The yeast lysate antigen 48938
was a reactive antigen for the detection of both IgG (mean absorbance value range: 1.198–2.934) and IgM (mean absorbance value
range: 0.505–0.845). For the same sera, antigen T-27 was also effective in the detection of IgG (mean absorbance value range:
0.904–3.356) and antigen 48089 was useful for the detection of IgM (mean absorbance value range: 0.377–0.554). The yeast lysate
antigen B5894 proved to be a poor antigen for the detection of both IgG and IgM (mean absorbance value ranges: 0.310–0.744
for IgG, 0.025–0.069 for IgM). Inherent variations in yeast lysate antigens such as these may be utilized to develop improved
immunoassay procedures for the specific detection of IgG or IgM in cases of blastomycosis. 相似文献
6.
Study of sugarcane pieces as yeast supports for ethanol production from sugarcane juice and molasses
Liang L Zhang YP Zhang L Zhu MJ Liang SZ Huang YN 《Journal of industrial microbiology & biotechnology》2008,35(12):1605-1613
Due to the environmental concerns and the increasing price of oil, bioethanol was already produced in large amount in Brazil
and China from sugarcane juice and molasses. In order to make this process competitive, we have investigated the suitability
of immobilized Saccharomyces cerevisiae strain AS2.1190 on sugarcane pieces for production of ethanol. Electron microscopy clearly showed that cell immobilization
resulted in firm adsorption of the yeast cells within subsurface cavities, capillary flow through the vessels of the vascular
bundle structure, and attachment of the yeast to the surface of the sugarcane pieces. Repeated batch fermentations using sugarcane
supported-biocatalyst were successfully carried out for at least ten times without any significant loss in ethanol production
from sugarcane juice and molasses. The number of cells attached to the support increased during the fermentation process,
and fewer yeast cells leaked into fermentation broth. Ethanol concentrations (about 89.73–77.13 g/l in average value), and
ethanol productivities (about 59.53–62.79 g/l d in average value) were high and stable, and residual sugar concentrations
were low in all fermentations (0.34–3.60 g/l) with conversions ranging from 97.67–99.80%, showing efficiency (90.11–94.28%)
and operational stability of the biocatalyst for ethanol fermentation. The results of this study concerning the use of sugarcane
as yeast supports could be promising for industrial fermentations.
L. Liang and Y. Zhang have contributed equally to this work. 相似文献
7.
Secondary central nervous system (CNS) blastomycosis is an unusual manifestation of blastomycosis. We report a case of recurrent
intracerebral blastomycosis that presented histopathologically with giant yeast-like cells and multinucleation that mimicked
Coccidioides immitis. The yeast forms of Blastomyces dermatitidis usually range in size from 8 to 20 μm in diameter. Large or giant yeast forms (20–40 μm) are rare. The four cases previously
reported in the literature involving giant yeast cell forms of B. dermatitidis are reviewed here. Intracerebral blastomycosis should be suspected in patients with signs and symptoms of CNS lesions and
histories of primary blastomycosis, or treatment with corticosteroids, or comprised immune systems. The diagnosis should be
confirmed by culture which presents typical biphasic microbiologic features. 相似文献
8.
Mariya V. Kovaleva Evgeniya I. Sukhanova Tatyana A. Trendeleva Marina V. Zyl’kova Ludmila A. Ural’skaya Kristina M. Popova Nils-Erik L. Saris Renata A. Zvyagilskaya 《Journal of bioenergetics and biomembranes》2009,41(3):239-249
In this study we used tightly-coupled mitochondria from Yarrowia lipolytica and Dipodascus (Endomyces) magnusii yeasts, possessing a respiratory chain with the usual three points of energy conservation. High-amplitude swelling and collapse
of the membrane potential were used as parameters for demonstrating induction of the mitochondrial permeability transition
due to opening of a pore (mPTP). Mitochondria from Y. lipolytica, lacking a natural mitochondrial Ca2+ uptake pathway, and from D. magnusii, harboring a high-capacitive, regulated mitochondrial Ca2+ transport system (Bazhenova et al. J Biol Chem 273:4372–4377, 1998a; Bazhenova et al. Biochim Biophys Acta 1371:96–100, 1998b; Deryabina and Zvyagilskaya Biochemistry (Moscow) 65:1352–1356, 2000; Deryabina et al. J Biol Chem 276:47801–47806, 2001) were very resistant to Ca2+ overload. However, exposure of yeast mitochondria to 50–100 μM Ca2+ in the presence of the Ca2+ ionophore ETH129 induced collapse of the membrane potential, possibly due to activation of the fatty acid-dependent Ca2+/nH+-antiporter, with no classical mPTP induction. The absence of response in yeast mitochondria was not simply due to structural
limitations, since large-amplitude swelling occurred in the presence of alamethicin, a hydrophobic, helical peptide, forming
voltage-sensitive ion channels in lipid membranes. Ca2+- ETH129-induced activation of the Ca2+/H+-antiport system was inhibited and prevented by bovine serum albumin, and partially by inorganic phosphate and ATP. We subjected
yeast mitochondria to other conditions known to induce the permeability transition in animal mitochondria, i.e., Ca2+ overload (in the presence of ETH129) combined with palmitic acid (Mironova et al. J Bioenerg Biomembr 33:319–331, 2001; Sultan and Sokolove Arch Biochem Biophys 386:37–51, 2001), SH-reagents, carboxyatractyloside (an inhibitor of the ADP/ATP translocator), depletion of intramitochondrial adenine nucleotide
pools, deenergization of mitochondria, and shifting to acidic pH values in the presence of high phosphate concentrations.
None of the above-mentioned substances or conditions induced a mPTP-like pore. It is thus evident that the permeability transition
in yeast mitochondria is not coupled with Ca2+ uptake and is differently regulated compared to the mPTP of animal mitochondria. 相似文献
9.
Shokrollahzadeh S Bonakdarpour B Vahabzadeh F Sanati M 《Journal of industrial microbiology & biotechnology》2007,34(1):17-25
The effect of phosphate (P
i
) concentration on the growth behavior of Saccharomyces cerevisiae strain CEN.PK113-5D in phosphate-limited batch and chemostat cultures was studied. The range of dilution rates used in the present study was 0.08–0.45 h−1. The batch growth of yeast cells followed Monod relationship, but growth of the cells in phosphate-limited chemostat showed change in growth kinetics with increasing dilution rates. The difference in growth kinetics of the yeast cells in phosphate-limited chemostat for dilution rates below and above approximately 0.2 h−1 has been discussed in terms of the batch growth kinetic data and the change in the metabolic activity of the yeast cells. Immunological detection of a C-terminally myc epitope-tagged Pho84 fusion protein indicated derepressive expression of the Pho84 high-affinity P
i
transporter in the entire range of dilution rates employed in this study. Phosphate transport activity mediated by Pho84 transporter was highest at very low dilution rates, i.e. 0.08–0.1 h−1, corresponding to conditions in which the amount of synthesized Pho84 was at its maximum. 相似文献
10.
Shen Tian Jinxin Zang Yaping Pan Jikai Liu Zhenhong Yuan Yongjie Yan Xiushan Yang 《Frontiers of Biology in China》2008,3(2):165-169
Candida shehatae gene xyl1 and Pichia stipitis gene xyl2, encoding xylose reductase (XR) and xylitol dehydrogenase (XD) respectively, were amplified by PCR. The genes xyl1 and xyl2 were placed under the control of promoter GAL in vector pYES2 to construct the recombinant expression vector pYES2-P12. Subsequently the vector pYES2-P12 was transformed
into S. cerevisiae YS58 by LiAc to produce the recombinant yeast YS58-12. The alcoholic ferment indicated that the recombinant yeast YS58-12
could convert xylose to ethanol with the xylose consumption rate of 81.3%.
__________
Translated from Microbiology, 2006, 33(3): 104–108 [译自:微生物学通报] 相似文献
11.
Sperstad S Lutnaes BF Stormo SK Liaaen-Jensen S Landfald B 《Journal of industrial microbiology & biotechnology》2006,33(4):269-273
A carotenoid-producing yeast strain, isolated from the sub-arctic, marine copepod Calanus finmarchicus, was identified as Rhodosporidium babjevae (Golubev) according to morphological and biochemical characteristics and phylogenetic inference from the small-subunit ribosomal
RNA gene sequence. The total carotenoids content varied with cultivation conditions in the range 66–117 μg per g dry weight.
The carotenoid pool, here determined for the first time, was dominated by torularhodin and torulene, which collectively constituted
75–91% of total carotenoids under various regimes of growth. β-Carotene varied in the range 5–23%. A high-peptone/low-yeast
extract (weight ratio 38:1) marine growth medium favoured the production of torularhodin, the carotenoid at highest oxidation
level, with an average of 63% of total carotenoids. In standard yeast medium (YM; ratio 1.7:1), torularhodin averaged 44%,
with increased proportions of the carotenes, torulene and β-carotene. The anticipated metabolic precursor γ-carotene (β,ψ-carotene)
constituted a minor fraction (≤8%) under all conditions of growth. 相似文献
12.
The cytosol, nuclei, vacuoles, and mitochondria of the yeast Saccharomyces cerevisiae possess inorganic polyphosphates (polyPs). PolyP levels, spectra of polyP chain lengths, and their dependence on the growth
phase are distinguished in the mentioned compartments. Inactivation of the PPX1 gene has no effect on the polyP metabolism under cultivation of the yeast in medium with glucose and 5–7 mM Pi. Inactivation of the PPN1 gene results in elimination of the high-molecular-mass exopolyphosphatases (∼120 to 830 kD) of the cytosol, nuclei, vacuoles,
and mitochondria of S. cerevisiae suggesting that it is just PPN1 that encodes these enzymes. Expression of the low-molecular-mass exopolyphosphatase of ∼45 kD encoded by the PPX1 gene decreases under PPN1 inactivation as well. While PPN1 inactivation has negligible effect on polyP levels, it results in increase in the long-chain polyPs in all the compartments
under study.
Published in Russian in Biokhimiya, 2006, Vol. 71, No. 11, pp. 1445–1450. 相似文献
13.
A new approach to the production of the recombinant SOD protein by methylotrophic <Emphasis Type="Italic">Pichia pastoris</Emphasis> 总被引:3,自引:0,他引:3
Yu P 《Applied microbiology and biotechnology》2007,74(1):93-98
The gene for the copper, zinc–superoxide dismutase (SOD) from the yeast Saccharomyces cerevisiae was cloned, characterized, and overexpressed in the methylotrophic Pichia pastoris. The sod gene sequence obtained is 465 bp and encodes 154 amino acid residues. The sod gene sequence was cloned into the pPIC9K vector, yielding pAB22. The linearized pAB22 DNA, digested with restriction enzyme
SacI, was transformed into the genome of the GS115 strain of yeast P. pastoris. The overexpressed SOD protein was shown to have immunologically biological activity and to be enzymatically active. The
SOD protein was purified from the cultured yeast by ammonium sulfate precipitation and diethylaminoethyl–cellulose column
chromatography. This relatively simple purification method produced a single band on analysis by sodium dodecyl sulfate polyacrylamide
gel electrophoresis (SDS-PAGE), which indicated that the SOD protein obtained attained to higher purity and specific activity. 相似文献
14.
Hongzhen Zhang Fengli Zhang Zhiyong Li 《World journal of microbiology & biotechnology》2009,25(7):1267-1274
Gene cloning, optimized production and property of marine lipase from Bacillus pumilus B106 associated with South China Sea sponge Halichondria rugosa were investigated in this paper. A lipase gene with whole ORF encoding 215 amino acids was obtained by PCR, protein domain
prediction suggested that the deduced lipase belongs to α/β hydrolases family. Based on single factor Seriatim-Factorial test
and Plackett–Burman experimental design, the optimal medium consisted of (per l) 12.5 ml maize oil, 5.0 g beef extract, 2.0 g
PO4
3− (0.6 g KH2PO4, 1.4 g K2HPO4), 17.15 g Mg2+, 5.0 g yeast extract, 2.282 g CaCl2 and 5.0 ml Tween80 with artificial sea water. Using this optimum medium, lipase activity and cell concentration were increased
by 3.54- and 1.31-fold over that of the basal medium, respectively. This lipase showed tolerance to high salinity, pH and
temperature. About 10–20% methanol exhibited a stimulatory effect on the lipase activity, while activity was inhibited by
30–40% methanol, 2-propanol, DMSO, and ethanol. This study provides a valuable resource for marine lipase production and extends
our understanding of the possible role of sponge-associated bacteria in the biotransformation of chemical compounds for the
sponge host. 相似文献
15.
Halotolerant yeast, Pichia farinosa, is a valuable yeast strain in fermentation industry because it produces high yield of glycerol and xylitol, and can tolerate both contamination and high-density growth during fermentation. However, the lack of genetic manipulation tools makes it less popular as a gene engineering strain. Expression systems commonly used in other yeast systems, such as Saccharomyces cerevisiae and Pichia pastoris cannot be used in P. farinosa because it translates universal Leu codon CUG as Ser. Here we reported a modified expression vector and a transformation system with enhanced efficiency in P. farinosa. The results showed that cells of OD600 0.8–1.0 with DTT treatment can obtain high transformation efficiency. The optimized electroporation condition was 900 V, 25 μF, and 200 Ω. The DNA concentration did not influence the transformation. Our system provides the potential not only for applying P. farinosa as an industrial strain of gene engineering, but also for studying gene function in its native host. 相似文献
16.
Ángeles Verástegui Julia Verde Santos García Norma Heredia Azucena Oranday Catalina Rivas 《World journal of microbiology & biotechnology》2008,24(7):1249-1252
The in vitro antimicrobial activity against pathogenic bacteria, yeast, and molds were examined in extracts of the Agave species A. lecheguilla, A. picta, A. scabra and A. lophanta using an agar diffusion technique. The extracts of A. picta produced zones of inhibition of 9–13 mm for E. coli, L. monocytogenes, S. aureus, and V. cholerae, while B. cereus and Y. enterocolitica were not inhibited. The other Agave species did not show any detectable inhibitory activity against the bacteria tested; however, all four Agave sp. were inhibitory against all yeast and molds analyzed as evident by 9–20 mm zones of inhibition. The minimum microbicidal
concentration (MMC) of the active extract ranged from 1.8 to 7.0 mg/ml for the sensitive bacteria, and 2.0–3.0 mg/ml for yeast.
In the case of molds, the minimum inhibitory concentration (MIC) of the active extracts ranged from 3.0 to 6.0 mg/ml. Together,
these data suggest that the Agave sp. analyzed are potential antimicrobial candidates with a broad range of activity. 相似文献
17.
Förster A Jacobs K Juretzek T Mauersberger S Barth G 《Applied microbiology and biotechnology》2007,77(4):861-869
The yeast Yarrowia lipolytica secretes high amounts of various organic acids, like citric (CA) and isocitric (ICA) acids, triggered by growth limitation
caused by different factors and an excess of carbon source. Depending on the carbon source used, Y. lipolytica strains produce a mixture of CA and ICA in a characteristic ratio. To examine whether the CA/ICA product ratio can be influenced
by gene-dose-dependent overexpression or by disruption of the isocitrate lyase (ICL)-encoding gene ICL1, recombinant Y. lipolytica strains were constructed, which harbour multiple ICL1 copies or a defective icl1 allele. The high-level expression of ICL in ICL1 multicopy integrative transformants resulted in a strong shift of the CA/ICA ratio into direction of CA. On glycerol, glucose
and sucrose, the ICA proportion decreased from 10–12% to 3–6%, on sunflower oil or hexadecane even from 37–45% to 4–7% without
influencing the total amount of acids (CA and ICA) produced. In contrast, the loss of ICL activity in icl1-defective strains resulted in a moderate 2–5% increase in the ICA proportion compared to ICL wild-type strains on glucose
or glycerol. 相似文献
18.
Holz M Förster A Mauersberger S Barth G 《Applied microbiology and biotechnology》2009,81(6):1087-1096
The yeast Yarrowia lipolytica secretes high amounts of various organic acids, like citric acid (CA) and isocitric acid (ICA) under an excess of carbon
source and several conditions of growth limitation. Depending on the carbon source used, Y. lipolytica strains produce a mixture of CA and ICA in a characteristic ratio. To examine whether this CA/ICA product ratio can be influenced
by gene–dose-dependent overexpression of aconitase (ACO)-encoding gene ACO1, a recombinant Y. lipolytica strain was constructed containing multiple copies of ACO1. The high-level expression of ACO in the ACO1 multicopy integrative transformant resulted in a shift of the CA/ICA product pattern into the direction of ICA. On sunflower
oil, a striking increase of the ICA proportion from 35–49% to 66–71% was observed compared to wild-type strains without influencing
the total amount of acids (CA and ICA) produced. On glycerol, glucose or sucrose, the ICA proportion increased only moderately
from 10–12% to 13–17%. This moderate shift into the direction of ICA was also observed in an icl1-defective strain. 相似文献
19.
Rufino RD Sarubbo LA Neto BB Campos-Takaki GM 《Journal of industrial microbiology & biotechnology》2008,35(8):907-914
The strategy of optimization using sequential factorial design was employed to enhance the tensio-active emulsifying agent
produced by Candida lipolytica using soybean oil refinery residue as substrate. A full factorial design was used to evaluate the impact of three fermentation
factors—amounts of refinery residue, glutamic acid and yeast extract. This allowed exclusion of the yeast extract. Full factorials
designs were then sequentially used to optimize the levels of the residue and glutamic acid. The surface tension value was
finally reduced to 25.29 mN/m. The maximum emulsifier activity using different substrates was within 40 h of cultivation.
The surface tension of the cell-free broth containing the biosurfactant remained very stable during exposure to a wide range
of pH (2–12), temperatures (0–120°C) and salinity (2–10% NaCl). The combination of an industrial waste and a cheap substrate
therefore seems to be very promising for the low-cost production of potent biosurfactant. 相似文献
20.
We examined the effects of genetic transformation by Agrobacterium rhizogenes on the production of tylophorine, a phenanthroindolizidine alkaloid, in the Indian medicinal plant, Tylophora indica. Transformed roots induced by the bacterium grew in axenic culture and produced shoots or embryogenic calli in the absence of hormone treatments. However, hormonal treatment was required to regenerate shoots in root explants of wild type control plants. Transformed plants showed morphological features typically seen in transgenic plants produced by A. rhizogenes, which include, short internodes, small and wrinkled leaves, more branches and numerous plagiotropic roots. Plants regenerated from transformed roots showed increased biomass accumulation (350–510% in the roots and 200–320% in the whole plants) and augmented tylophorine content (20–60%) in the shoots, resulting in a 160–280% increase in tylophorine production in different clones grown in vitro. 相似文献