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1.
Prasongsuk S Berhow MA Dunlap CA Weisleder D Leathers TD Eveleigh DE Punnapayak H 《Journal of industrial microbiology & biotechnology》2007,34(1):55-61
Tropical isolates of Aureobasidium pullulans previously isolated from distinct habitats in Thailand were characterized for their capacities to produce the valuable polysaccharide, pullulan. A. pullulans strain NRM2, the so-called “color variant” strain, was the best producer, yielding 25.1 g pullulan l−1 after 7 days in sucrose medium with peptone as the nitrogen source. Pullulan from strain NRM2 was less pigmented than those from the other strains and was remarkably pure after a simple ethanol precipitation. The molecular weight of pullulan from all cultures dramatically decreased after 3 days growth, as analyzed by high performance size exclusion chromatography. Alpha-amylase with apparent activity against pullulan was expressed constitutively in sucrose-grown cultures and induced in starch-grown cultures. When the alpha-amylase inhibitor acarbose was added to the culture medium, pullulan of slightly higher molecular weight was obtained from late cultures, supporting the notion that alpha-amylase plays a role in the reduction of the molecular weight of pullulan during the production phase.Names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard of the product, and the use of the name by the USDA implies no approval of the product to the exclusion of others that may also be suitable. 相似文献
2.
Timothy D. Leathers Joseph O. Rich Melinda S. Nunnally Amber M. Anderson 《Biotechnology letters》2018,40(1):157-163
Objective
To test the inactivation of the antibiotic, virginiamycin, by laccase-induced culture supernatants of Aureobasidium pullulans.Results
Fourteen strains of A. pullulans from phylogenetic clade 7 were tested for laccase production. Three laccase-producing strains from this group and three previously identified strains from clade 5 were compared for inactivation of virginiamycin. Laccase-induced culture supernatants from clade 7 strains were more effective at inactivation of virginiamycin, particularly at 50 °C. Clade 7 strain NRRL Y-2567 inactivated 6 µg virginiamycin/ml within 24 h. HPLC analyses indicated that virginiamycin was degraded by A. pullulans.Conclusions
A. pullulans has the potential for the bioremediation of virginiamycin-contaminated materials, such as distiller’s dry grains with solubles (DDGS) animal feed produced from corn-based fuel ethanol production.3.
From a survey of more than 50 diverse strains of Aureobasidium pullulans, 21 produced extracellular heavy oils. Most oil producers fell into phylogenetic clades 8, 9, and 11. Oil colors ranged from
bright yellow to malachite. More than half of the strains produced oil that was fluorescent. In medium containing 5% (w/v)
sucrose, oil yields ranged from 0.5 to 6 g oil/l. Strain CU 43 reached stationary growth phase at day 4 while oil yields were
maximal at day 6. CU 43 produced bright yellow, highly fluorescent oil that also was visible as intracellular droplets under
fluorescent microscopy. Oil was surface active, suggesting that it functions as a biosurfactant. Oil from two strains (CU
43 and NRRL Y-12974) differentially inhibited mammalian cancer cell lines. MALDI-TOF MS spectra suggested that A. pullulans strains produce a family of related oil structures. 相似文献
4.
Joseph O. Rich Pennapa Manitchotpisit Stephen W. Peterson Siqing Liu Timothy D. Leathers Amber M. Anderson 《Biotechnology letters》2016,38(5):863-870
Objective
The objective was to phylogenetically classify diverse strains of Aureobasidium pullulans and determine their production of feruloyl esterase.Results
Seventeen strains from the A. pullulans literature were phylogenetically classified. Phenotypic traits of color variation and endo-β-1,4-xylanase overproduction were associated with phylogenetic clade 10 and particularly clade 8. Literature strains used for pullulan production all belonged to clade 7. These strains and 36 previously classified strains were tested for feruloyl esterase production, which was found to be associated with phylogenetic clades 4, 11, and particularly clade 8. Clade 8 strains NRRL 58552 and NRRL 62041 produced the highest levels of feruloyl esterase among strains tested.Conclusions
Production of both xylanase and feruloyl esterase are associated with A. pullulans strains in phylogenetic clade 8, which is thus a promising source of enzymes with potential biotechnological applications.5.
West TP 《Folia microbiologica》2011,56(4):335-338
Fungal cells of Aureobasidium pullulans ATCC 201253 were immobilized by entrapment in chitosan beads, and the immobilized cells were investigated for their ability
to produce the polysaccharide pullulan using batch fermentation. The 1% chitosan-entrapped fungal cells were capable of producing
pullulan for two cycles of 168 h using corn syrup as a carbon source. Pullulan production by the immobilized cells increased
by 1.6-fold during the second production cycle (5.0 g/l) relative to the first production cycle (3.1 g/l) with the difference
in production being statistically significant after 168 h. The productivity of the immobilized cells increased during the
second production cycle while its pullulan content decreased. The level of cell leakage from the support remained unchanged
for both production cycles. 相似文献
6.
Summary A variety of habitats were sampled for the presence of Aureobasidium black yeasts with the attempt to find pullulan-producing strains. Habitats included leaves of mango (Mangifera indica Linn.), tamarind (Tamarindus indica Linn.), asoka (Saraca indica Linn.) and latex-painted and bathroom cement-wall surfaces. Parameters for the identification of the isolates included morphology, nutritional parameters, exopolysaccharide (EPS) production, and rDNA internal transcribed spacer (ITS) sequencing. All isolates of black yeasts were polymorphic with blastospores, hyphae, and chlamydospores. ITS analyses showed strong correlation with the GenBankA. pullulanssequences, with alignment using BLAST yielding greater than 95% similarity. All five isolates tested produced pullulan as deduced from infrared spectra and sensitivity to pullulanase. None produced aubasidan as evidenced from their IR spectra. The current studies support the notion that the hot, humid environments facilitate the development of A. pullulansand its tropical variants in diverse phylloplane and walls habitats, and merit support for further isolation and characterization of these black yeasts as a source of unique pullulan-producing strains. 相似文献
7.
Winter wheat, grown under greenhouse conditions, was protected four times with a cell suspension of Aureobasidium pullulans var. pullulans during the growing season. After harvest, the distribution and survival rates of the studied biocontrol agent were analyzed under a scanning electron microscope. The abundance of filamentous fungi, yeasts, pseudomonads and Azotobacter bacteria was determined by inoculation onto selective agar media. A. pullulans produced mostly unicellular chlamydospores on the surface and in the brush of kernels. Multicellular blastospore conglomerates secreted extracellular polymeric substances (EPS), and their biofilms were found in the brush and crease of kernels. The application of a cell suspension of A. pullulans with the density of 104 CFU to winter wheat spikes, repeated four times, inhibited the growth of pseudomonads, Azotobacter bacteria and filamentous fungi. 相似文献
8.
Sehanat Prasongsuk Pongtharin Lotrakul Imran Ali Wichanee Bankeeree Hunsa Punnapayak 《Folia microbiologica》2018,63(2):129-140
Different strains of the saprophytic yeast-like fungus Aureobasidium pullulans (Ascomycota: Dothideales) exhibit different biochemical characteristics, while their ubiquitous occurrence across diverse habitats and environmental conditions makes them an easily accessible source for biotechnological exploitation. They are useful in agricultural and industrial applications. Their antagonistic activities against postharvest pathogens make them suitable bioagents for the postharvest preservation of fruits and vegetables, while they possess antimicrobial activities against bacteria and fungi. Additionally, A. pullulans appears to be a potent source of single-cell protein. Many strains of A. pullulans harbor a wide range of industrially important enzymes, while the trademark exopolysaccharide pullulan that they produce has been extensively studied and is currently used in many applications. They also produce poly (β-l-malic acid), heavy oil liamocins, siderophore, and aubasidan-like β-glucan which are of interest for future applications. Ongoing studies suggest that A. pullulans holds many more interesting properties capable of further potential biotechnological applications. 相似文献
9.
Timothy D. Leathers Neil P. J. Price Pennapa Manitchotpisit Kenneth M. Bischoff 《World journal of microbiology & biotechnology》2016,32(12):199
Liamocins are unique heavier-than-water “oils” produced by certain strains of the fungus Aureobasidium pullulans. Liamocins have antibacterial activity with specificity for Streptococcus sp. Previous studies reported that liamocin yields were highest from strains of A. pullulans belonging to phylogenetic clades 8, 9, and 11, cultured on medium containing sucrose. In this study, 27 strains from these clades were examined for the first time for production of liamocins from agricultural biomass substrates. Liamocin yields were highest from strains in phylogenetic clade 11, and yields were higher from cultures grown on sucrose than from those grown on pretreated wheat straw. However, when supplementary enzymes (cellulase, β-glucosidase, and xylanase) were added, liamocin production on pretreated wheat straw was equivalent to that on sucrose. Liamocins produced from wheat straw were free of the melanin contamination common in sucrose-grown cultures. Furthermore, MALDI-TOF MS analysis showed that liamocins produced from wheat straw were under-acetylated, resulting in higher proportions of the mannitol A1 and B1 species of liamocin, the latter of which has the highest biological activity against Streptococcus sp. 相似文献
10.
Characterization of<Emphasis Type="Italic"> Aureobasidium pullulans</Emphasis> isolated from airborne spores in Thailand 总被引:1,自引:0,他引:1
Punnapayak H Sudhadham M Prasongsuk S Pichayangkura S 《Journal of industrial microbiology & biotechnology》2003,30(2):89-94
Isolates from air in several locations in Thailand were identified as Aureobasidium pullulans PR with dark pigmentation (Loei province), A. pullulans SU with an unusual conidial apparatus (Chiangmai province), and A. pullulans CU with burgundy-red pigmentation (from a shady area in Bangkok). The internal transcribed spacer sequences of the rDNA of A. pullulans SU and A. pullulans CU confirmed that they were A. pullulans. Both A. pullulans CU and A. pullulans PR preferred 30 °C and pH 7.5 for exopolysaccharide (EPS) production, while A. pullulans SU preferred 25 °C and pH 6.5. All three isolates preferred glucose over sucrose and (NH4)2SO4 over peptone for EPS production. Under optimal conditions, A. pullulans PR produced EPS yields of up to 0.225 g g−1, followed by A. pullulans CU (0.185 g g−1) and A. pullulans SU (0.158 g g−1). Amylase activities were detected during the course of EPS production but gradually decreased as the EPS yields increased.
IR spectra suggest that the EPS from these isolates was pullulan. EPS from the three isolates were partially sensitive to
pullulanase.
Electronic Publication 相似文献
11.
Mounir R Durieux A Bodo E Allard C Simon JP Achbani EH El-Jaafari S Douira A Jijakli MH 《Biotechnology letters》2007,29(4):553-559
Aureobasidium pullulans (de Bary) Arnaud (Ach 1-1) was grown in a glucose fed-batch fermentor to 106 g dry wt l−1 in 48 h. The cells were dried in a fluidized bed dryer with a final viability of 62%. After 7 months at 4°C, the viability
was 28% of the initial value (= 2.3 × 1010 c.f.u. g−1 dry matter). A protection level of 89% was achieved with the biomass preparation at 1 × 108 c.f.u. ml−1 after 28 and 7 days for apples stored respectively at 5 and 25°C against Penicillium expansum. Our process is suitable to produce large quantities of the strain Ach 1-1 as biological control agent for apple preservation. 相似文献
12.
Kazuyoshi Ohta Hidenori Tanaka Daisuke Yamakawa Hironori Hamasuna Hirohisa Fujimoto 《Journal of industrial microbiology & biotechnology》2011,38(8):967-973
An extracellular xylanase XynI of glycoside hydrolase family 11 from the dimorphic fungus Aureobasidium pullulans ATCC 20524 possesses an N-terminal extension of 34 amino acids (Ohta et al., J. Biosci. Bioeng. 92:262–270, 2001). The N-terminal
extension includes three sites (Ala-X-Ala-X-Ala-X-Ala) that are potentially cleavable by signal peptidase I of Escherichia
coli. The A. pullulans
xynI signal sequence was fused in frame to the mature protein region of the equivalent xylanase gene xynA from the filamentous fungus Penicillium citrinum. The gene fusion xynI::A was inserted into the plasmid pET-26b(+) to yield pEXP401. An E. coli BL21(DE3) transformant harboring the pEXP401 exhibited xylanase activity (per ml of the culture) of 16.8 U in the fraction
of culture supernatant as well as 4.29 U in the fraction of cell-free extract after 12 h of growth with isopropyl-β-d-thiogalactopyranoside at 30°C. N-terminal amino acid sequence analysis of the secreted recombinant proteins revealed cleavage
at four distinct sites within the N-terminal extension of XynI, two of which conformed to the Ala-X-Ala motif prior to the
cleavage site. The XynA proteins secreted into the culture medium showed high specific activities from 506 to 651 U/mg, which
were twofold higher than that of the native enzyme. 相似文献
13.
Continuous production of fructooligosaccharides (FOS) by Aureobasidium pullulans immobilized on calcium alginate beads with a packed bed was investigated at a plant scale reactor. Optimum conditions were
with 770 g sucrose/l, being fed at 200 l/h at 50°C which gave a productivity of 180 g FOS/l h. Initial activity was maintained
for more than 100 days. The reactor was successfully scaled up to a production scale of 1.2 m3. 相似文献
14.
Tashiro Y Kaneko W Sun Y Shibata K Inokuma K Zendo T Sonomoto K 《Applied microbiology and biotechnology》2011,89(6):1741-1750
We isolated and characterized a d-lactic acid-producing lactic acid bacterium (d-LAB), identified as Lactobacillus delbrueckii subsp. lactis QU 41. When compared to Lactobacillus coryniformis subsp. torquens JCM 1166 T and L. delbrueckii subsp. lactis JCM 1248 T, which are also known as d-LAB, the QU 41 strain exhibited a high thermotolerance and produced d-lactic acid at temperatures of 50 °C and higher. In order to optimize the culture conditions of the QU 41 strain, we examined
the effects of pH control, temperature, neutralizing reagent, and initial glucose concentration on d-lactic acid production in batch cultures. It was found that the optimal production of 20.1 g/l d-lactic acid was acquired with high optical purity (>99.9% of d-lactic acid) in a pH 6.0-controlled batch culture, by adding ammonium hydroxide as a neutralizing reagent, at 43 °C in MRS
medium containing 20 g/l glucose. As a result of product inhibition and low cell density, continuous cultures were investigated
using a microfiltration membrane module to recycle flow-through cells in order to improve d-lactic acid productivity. At a dilution rate of 0.87 h−1, the high cell density continuous culture exhibited the highest d-lactic acid productivity of 18.0 g/l/h with a high yield (ca. 1.0 g/g consumed glucose) and a low residual glucose (<0.1 g/l)
in comparison with systems published to date. 相似文献
15.
16.
The extracellular lipase structural gene was isolated from cDNA of Aureobasidium pullulans HN2-3 by using SMARTTM RACE cDNA amplification kit. The gene had an open reading frame of 1245 bp long encoding a lipase. The coding region of the
gene was interrupted by only one intron (55 bp). It encodes 414 amino acid residues of a protein with a putative signal peptide
of 26 amino acids. The protein sequence deduced from the extracellular lipase structural gene contained the lipase consensus
sequence (G-X-S-X-G) and three conserved putative N-glycosylation sites. According to the phylogenetic tree of the lipases,
the lipase from A. pullulans was closely related to that from Aspergillus fumigatus (XP_750543) and Neosartorya fischeri (XP_001257768) and the identities were 50% and 52%, respectively. The mature peptide encoding cDNA was subcloned into pET-24a
(+) expression vector. The recombinant plasmid was expressed in Escherichia coli BL21(DE3). The expressed fusion protein was analyzed by SDS-PAGE and western blotting and a specific band with molecular
mass of about 47 kDa was found. Enzyme activity assay verified the recombinant protein as a lipase. A maximum activity of
0.96 U/mg was obtained from cellular extract of E. coli BL21(DE3) harboring pET-24a(+)LIP1. Optimal pH and temperature of the crude recombinant lipase were 8.0 and 35 °C, respectively and the crude recombinant lipase
had the highest hydrolytic activity towards peanut oil. 相似文献
17.
Ö. Şimşek N. Akkoç A. H. Çon F. Özçelik P. E. J. Saris Mustafa Akçelik 《Journal of industrial microbiology & biotechnology》2009,36(6):863-871
Nisin production in continuous cultures of bioengineered Lactococcus lactis strains that incorporate additional immunity and regulation genes was studied. Highest nisin activities were observed at
0.2 h–1 dilution rate and 12.5 g l–1 fructose concentration for all strains. Recombinant strains were able to produce greater amounts of nisin at dilution rates
below 0.3 h−1 compared to the control strain. However, this significant difference disappeared at dilution rates of 0.4 and 0.5 h–1. For the strains LL27, LAC338, LAC339, and LAC340, optimum conditions for nisin production were determined to be at 0.29,
0.26, 0.27, and 0.27 h–1 dilution rates and 11.95, 12.01, 11.63, and 12.50 g l–1 fructose concentrations, respectively. The highest nisin productivity, 496 IU ml–1 h–1, was achieved with LAC339. The results of this study suggest that low dilution rates stabilize the high specific nisin productivity
of the bioengineered strains in continuous fermentation. Moreover, response surface methodology analysis showed that regulation
genes yielded high nisin productivity at wide ranges of dilution rates and fructose concentrations. 相似文献
18.
Two repeated DNA sequences isolated from a partial genomic DNA library of Helianthus annuus, p HaS13 and p HaS211, were shown to represent portions of the int gene of a Ty3 /gypsy retroelement and of the RNase-Hgene of a Ty1 /copia retroelement, respectively. Southern blotting patterns obtained by hybridizing the two probes to BglII- or DraI-digested genomic DNA from different Helianthus species showed p HaS13 and p HaS211 were parts of dispersed repeats at least 8 and 7 kb in length, respectively, that were conserved in all species studied. Comparable hybridization patterns were obtained in all species with p HaS13. By contrast, the patterns obtained by hybridizing p HaS211 clearly differentiated annual species from perennials. The frequencies of p HaS13- and p HaS211-related sequences in different species were 4.3x10(4)-1.3x10(5) copies and 9.9x10(2)-8.1x10(3) copies per picogram of DNA, respectively. The frequency of p HaS13-related sequences varied widely within annual species, while no significant difference was observed among perennial species. Conversely, the frequency variation of p HaS211-related sequences was as large within annual species as within perennials. Sequences of both families were found to be dispersed along the length of all chromosomes in all species studied. However, Ty3 /gypsy-like sequences were localized preferentially at the centromeric regions, whereas Ty1/ copia-like sequences were less represented or absent around the centromeres and plentiful at the chromosome ends. These findings suggest that the two sequence families played a role in Helianthusgenome evolution and species divergence, evolved independently in the same genomic backgrounds and in annual or perennial species, and acquired different possible functions in the host genomes. 相似文献
19.
The excretion of the aromatic amino acid l-tyrosine was achieved by manipulating three gene targets in the wild-type Escherichia coli K12: The feedback-inhibition-resistant (fbr) derivatives of aroG and tyrA were expressed on a low-copy-number vector, and the TyrR-mediated regulation of the aromatic amino acid biosynthesis was
eliminated by deleting the tyrR gene. The generation of this l-tyrosine producer, strain T1, was based only on the deregulation of the aromatic amino acid biosynthesis pathway, but no
structural genes in the genome were affected. A second tyrosine over-producing strain, E. coli T2, was generated considering the possible limitation of precursor substrates. To enhance the availability of the two precursor
substrates phosphoenolpyruvate and erythrose-4-phosphate, the ppsA and the tktA genes were over-expressed in the strain T1 background, increasing l-tyrosine production by 80% in 50-ml batch cultures. Fed-batch fermentations revealed that l-tyrosine production was tightly correlated with cell growth, exhibiting the maximum productivity at the end of the exponential
growth phase. The final l-tyrosine concentrations were 3.8 g/l for E. coli T1 and 9.7 g/l for E. coli T2 with a yield of l-tyrosine per glucose of 0.037 g/g (T1) and 0.102 g/g (T2), respectively. 相似文献
20.
KiBeom Lee 《World journal of microbiology & biotechnology》2007,23(9):1317-1320
Lactobacillus
delbrueckii subsp. lactis strains were developed having increased activity, by gradually acclimatizing the bacteria to acidic conditions over repeated
batch culture. Cells from one batch culture were used as the inoculum for the subsequent batch culture and thereby an adapted
strain of Lactobacillus was obtained showing improved lactic acid productivity, cell growth and total glucose utilization. Furthermore, the acclimatized
cells used significantly less nitrogen for a given level of lactic acid production, which is significant from an industrial
point of view. The developed procedure decreases fermentation time and nutrient use, leading to reduced operation costs, while
providing a lactic acid yield superior to previously reported methods. 相似文献