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1.
Jin Fujita Hisashi Fukuda Yu-ichi Yamane Yasuzo Kizaki Seiko Shigeta Kazuhisa Ono Osamu Suzuki Saburo Wakabayashi 《Biotechnology letters》2001,23(11):867-871
The high phytase producing mutant of Aspergillus oryzae (KL-38) previously isolated was employed for koji making, and the produced koji rice then supplied for sake brewing. The alcohol fermentation was improved compared to that with the parent strain (A. oryzae BP-1). The effects of two phytase isozymes (Phy I and Phy II) produced by A. oryzae on yeast growth and inorganic phosphate liberation were investigated using a synthetic medium containing phytic acid as a sole phosphate source. Yeast growth and the liberation of inorganic phosphate were both enhanced by the combination of Phy I and Phy II at a ratio of 1 to 3, which was compatible with the production ratio in KL-38. Based on these results, phytase plays important role in sake brewing, and that the maximum inorganic phosphate liberation from phytic acid can be obtained by a suitable combination of Phy I and Phy II. 相似文献
2.
The thermotolerant fungus, Aspergillus niger NCIM 563, was used for production of extracellular phytase on agricultural residues: wheat bran, mustard cake, cowpea meal,
groundnut cake, coconut cake, cotton cake and black bean flour in solid state fermentation (SSF). Maximum enzyme activity
(108 U g−1 dry mouldy bran, DMB) was obtained with cowpea meal. During the fermentation phytic acid was hydrolysed completely with a
corresponding increase in biomass and phytase activity within 7 days. Phosphate in the form of KH2PO4 (10 mg per 100 g of agriculture residue) increased phytase activity. Among various surfactants added to SSF, Trition X-100
(0.5%) exhibited a 30% increase in phytase activity. The optimum pH and temperature of the crude enzyme were 5.0 and 50°C
respectively. Phytase activity (86%) was retained in buffer of pH 3.5 for 24 h. The enzyme retained 75% of its activity on
incubation at 55°C for 1 h. In the presence of 1 mM K+ and Zn2+, 95% and 55% of the activity were retained. Scanning electron microscopy showed a high density growth of fungal mycelia on
wheat bran particles during SSF. Journal of Industrial Microbiology & Biotechnology (2000) 24, 237–243.
Received 07 June 1999/ Accepted in revised form 18 December 1999 相似文献
3.
Myung Hoon Song Ju-young Nah Yeon Soo Han Dong Min Han Keon-Sang Chae 《Biotechnology letters》2001,23(9):689-691
Addition of KCl to medium at 0.1 M or higher promoted the formation of conidial heads in Aspergillus oryzae. When higher concentrations of KCl were added, a larger number of conidial heads were formed. NaCl and MgCl2 were slightly less effective than KCl. The effect of salt on the formation of conidial heads on a minimal medium was as high as on a potato/dextrose medium but slightly higher than that on a complex medium when 1 M KCl was added. 相似文献
4.
High-level expression, purification and characterization of recombinant Aspergillus oryzae alkaline protease in Pichia pastoris 总被引:1,自引:0,他引:1
The alkaline protease gene from Aspergillus oryzae was cloned, and then it was successfully expressed in the heterologous Pichia pastoris GS115 with native signal peptide or α-factor secretion signal peptide. The yield of the recombinant alkaline protease with native signal peptide was about 1.5-fold higher than that with α-factor secretion signal peptide, and the maximum yield of the recombinant alkaline protease was 513 mg/L, which was higher than other researches. The recombinant alkaline protease was purified by ammonium sulfate precipitation, ion exchange chromatography and gel filtration chromatography. The purified recombinant alkaline protease showed on SDS–PAGE as a single band with an apparent molecular weight of 34 kDa. The recombinant alkaline protease was identical to native alkaline protease from A. oryzae with regard to molecular weight, optimum temperature for activity, optimum pH for activity, stability to pH, and similar sensitivity to various metal ions and protease inhibitors. The native enzyme retained 61.18% of its original activity after being incubated at 50 °C for 10 min, however, the recombinant enzyme retained 56.22% of its original activity with same disposal. The work demonstrates that alkaline protease gene from A. oryzae can be expressed largely in P. pastoris without affecting its enzyme properties and the recombinant alkaline protease could be widely used in various industrial applications. 相似文献
5.
6.
FI-Carboxymethylcellulase (cmc1; family 12) is one of the endoglucanases of Aspergillus aculeatus and consists of single polypeptide chain of 221 amino acids. The cmc1 gene was expressed in Aspergillus oryzae niaD300 (niaD−) under promoter 8142. The plasmid pCMG14 carrying the cmc1 gene at PstI site was used as a source of the gene (920 bp) and Aspergillus oryzae was successfully transformed by the plasmid pNAN-cmc1 (harboring cmc1 gene). The plasmid was integrated in Aspergillus oryzae niaD300 genome at niaD locus and the transformed fungus constitutively produced very high amounts of endoglucanases when grown on glucose, maltose,
soluble starch and wheat bran. 相似文献
7.
Biotransformation of piceid in Polygonum cuspidatum to resveratrol by Aspergillus oryzae 总被引:1,自引:0,他引:1
Wang H Liu L Guo YX Dong YS Zhang DJ Xiu ZL 《Applied microbiology and biotechnology》2007,75(4):763-768
Biotransformation of piceid in Polygonum cuspidatum to resveratrol by Aspergillus oryzae was investigated in this study. Resveratrol is widely used in medicine, food, and cosmetic because of its pharmacological
properties. However, it has a much lower content in plants compared with its glucoside piceid, which has a much lower bioavailability.
Traditionally, the aglycone is acquired by acid or enzymatic hydrolysis of its glucoside, but the violent condition and the
acid pollution in hydrolytic reaction and the high cost of the enzyme limit their industrial development. In this paper, fermentation
of P. cuspidatum by A. oryzae was successfully performed, during which, piceid was converted to resveratrol with the highest yield of trans-resveratrol 1.35%, 3.6 times higher than that obtained from raw herb by microwave-assisted extraction. Scale-up production
was also performed and the yield of trans-resveratrol was 3.1 times higher after 24 h incubation. Therefore, biotransformation is a better method to increase the yield
of resveratrol because of its high yield and mild conditions. 相似文献
8.
Repeated-batch production of kojic acid in a cell-retention fermenter using Aspergillus oryzae M3B9 总被引:1,自引:0,他引:1
Wan HM Chen CC Giridhar R Chang TS Wu WT 《Journal of industrial microbiology & biotechnology》2005,32(6):227-233
A cell-retention fermenter was used for the pilot-scale production of kojic acid using an improved strain of Aspergillus oryzae in repeated-batch fermentations. Among the various carbon and nitrogen sources used, sucrose and yeast extract promoted pellet morphology of fungi and higher kojic acid production. Repeated-batch culture using a medium replacement ratio of 75% gave a productivity of 5.3 g L–1 day–1 after 11.5 days of cultivation. While batch culture in shake-flasks resulted in a productivity of 5.1 g L–1 day–1, a productivity of 5 g L–1 day–1 was obtained in a pilot-scale fermenter. By converting the batch culture into repeated batches, the non-productive downtime of cleaning, filling and sterilizing the fermenter between each batch were eliminated, thereby increasing the kojic acid productivity. 相似文献
9.
Takuya Koseki Akane Hori Shouji Seki Tetsuya Murayama Yoshihito Shiono 《Applied microbiology and biotechnology》2009,83(4):689-696
Two hypothetical proteins XP_001818628 and XP_001819091 (designated AoFaeB and AoFaeC, respectively), showing sequence identity
with known type-C feruloyl esterases, have been found in the genomic sequence of Aspergillus oryzae. We cloned the putative A. oryzae feruloyl esterase-encoding genes and expressed them in Pichia pastoris. Both purified recombinant AoFaeB (rAoFaeB) and AoFaeC (rAoFaeC) had apparent relative molecular masses of 61,000 and 75,000,
respectively, on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. After N-deglycosylation, both proteins had a relative molecular mass of 55,000. The optimum pH for rAoFaeB was 6.0, although it was
stable at pH values ranging from 3.0 to 9.0; rAoFaeC had an optimum pH of 6.0 and was stable in the pH range of 7.0–10.0.
Thermostability of rAoFaeC was greater than that of rAoFaeB. Whereas rAoFaeC displayed hydrolytic activity toward methyl caffeate,
methyl p-coumarate, methyl ferulate, and methyl sinapate, rAoFaeB displayed hydrolytic activity toward methyl caffeate, methyl p-coumarate, and methyl ferulate but not toward methyl sinapate. Substrate specificity profiling of rAoFaeB and rAoFaeC revealed
type-B and type-C feruloyl esterases, respectively. Ferulic acid was efficiently released from wheat arabinoxylan when both
esterases were applied with xylanase from Thermomyces lanuginosus. Both recombinant proteins also exhibited hydrolytic activity toward chlorogenic acid.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
10.
11.
By combining induced mutation, using NTG and UV irradiation, and protoplasting of a wild type strain of Aspergillus oryzae ATCC 22788, a hyper-producing strain was obtained that accumulated 41 g kojic acid l(-1) in shake-flasks, which was 100-fold higher than that in the wild type strains. Similar production of kojic acid was obtained in 5 l stirred-tank fermentations. 相似文献
12.
Jin FJ Watanabe T Juvvadi PR Maruyama J Arioka M Kitamoto K 《Applied microbiology and biotechnology》2007,76(5):1059-1068
In this study, we investigated the effects of proteinase gene disruption on heterologous protein production by Aspergillus oryzae. The human lysozyme (HLY) was selected for recombinant production as a model for the heterologous protein. A tandem HLY construct
fused with α-amylase (AmyB) was expressed by A. oryzae in which the Kex2 cleavage site was inserted at the upstream of HLY. HLY was successfully processed from AmyB and produced
in the medium. We performed a systematic disruption analysis of five proteinase genes (pepA, pepE, alpA, tppA, and palB) in the HLY-producing strain with the adeA selectable marker. Comparative analysis indicated that disruption of the tppA gene encoding a tripeptidyl peptidase resulted in the highest increase (36%) in the HLY production. We further deleted the
tppA gene in the pepE or palB disruptant with another selectable marker, argB. Consequently, a double disruption of the tppA and pepE genes led to a 63% increase in the HLY production compared to the control strain. This is the first study to report that
the double disruption of the tppA and pepE genes improved the production level of a heterologous protein by filamentous fungi.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
13.
Isolation and characterization of a phytase with improved properties from Citrobacter braakii 总被引:5,自引:0,他引:5
Citrobacter braakii YH-15 produced an intracellular phytase which was purified 12800 fold to homogeneity with the specific activity of 3457 units mg–1, which is 1.9 times higher than E. coli phytase previously recorded as having the highest specific activity. Its molecular weight was 47 kDa by SDS-PAGE gel. Enzyme activity was optimal at pH 4 and at 50 °C. The K
m value for sodium phytate was 0.46 mM with a V
max 6027 U mg–1. The phytase was resistant to proteases such as trypsin, pepsin, papain, pancreatin, and elastase. 相似文献
14.
Chipeta ZA du Preez JC Christopher L 《Journal of industrial microbiology & biotechnology》2008,35(6):587-594
The effects of cultivation pH and agitation rate on growth and extracellular xylanase production by Aspergillus oryzae NRRL 3485 were investigated in bioreactor cultures using spent sulphite liquor (SSL) and oats spelts xylan as respective carbon substrates. Xylanase production by this fungus was greatly affected by the culture pH, with pH 7.5 resulting in a high extracellular xylanase activity in the SSL-based medium as well as in a complex medium with xylan as carbon substrate. This effect, therefore, was not solely due to growth inhibition at the lower pH values by the acetic acid in the SSL. The xylanase activity in the SSL medium peaked at 199 U ml(-1) at pH 7.5 with a corresponding maximum specific growth rate of 0.39 h(-1). By contrast, the maximum extracellular beta-xylosidase activity pf 0.36 U ml(-1) was recorded at pH 4.0. Three low molecular weight xylanase isozymes were secreted at all pH values within the range of pH 4-8, whereas cellulase activity on both carbon substrates was negligible. Impeller tip velocities within the range of 1.56-3.12 m s(-1) had no marked effect, either on the xylanase activity, or on the maximum volumetric rate of xylanase production. These results also demonstrated that SSL constituted a suitable carbon feedstock as well as inducer for xylanase production in aerobic submerged culture by this strain of A. oryzae. 相似文献
15.
Systematic analysis of SNARE localization in the filamentous fungus Aspergillus oryzae 总被引:1,自引:0,他引:1
Kuratsu M Taura A Shoji JY Kikuchi S Arioka M Kitamoto K 《Fungal genetics and biology : FG & B》2007,44(12):1310-1323
In spite of their great importance for both applied and basic biology, studies on vesicular trafficking in filamentous fungi have been so far very limited. Here, we identified 21 genes, which might be a total set, encoding putative SNARE proteins that are key factors for vesicular trafficking, taking advantage of available whole genome sequence in the filamentous fungus Aspergillus oryzae. The subsequent systematic analysis to determine the localization of putative SNAREs using EGFP-fused chimeras revealed that most putative SNAREs show similar subcellular distribution to their counterparts in the budding yeast. However, there existed some characteristic features of SNAREs in A. oryzae, such as SNARE localization at/near the septum and the presence of apparently non-redundant plasma membrane Qa-SNAREs. Overall, this analysis allowed us to provide an overview of vesicular trafficking and organelle distribution in A. oryzae. 相似文献
16.
Converti A. Del Borghi M. Gandolfi R. Molinari F. Palazzi E. Zilli M. 《World journal of microbiology & biotechnology》2002,18(5):409-416
The results collected at different temperatures for ethanol acetylation by cell-bound carboxylesterase from lyophilized cells of Aspergillus oryzae have been used to investigate the kinetics and thermodynamics of this esterification in n-heptane. The occurrence of reversible unfolding followed by irreversible denaturation of the enzyme has been proposed to explain the increase in the starting rate of ethyl acetate formation with temperature observed up to 55 °C and the consequent fall beyond this threshold. The Arrhenius model has been used to estimate the apparent activation enthalpies of both the acetylation reaction (H
= 29–33 kJ mol–1) and reversible enzyme unfolding (H
u = 56–63 kJ mol–1). The results of residual activity tests performed with cells previously exposed at different temperatures for variable times enabled us also to estimate the first-order rate constant of irreversible denaturation (2.40 × 10–3 h–1 < k
d < 8.11 × 10–3 h–1) as well as the related thermodynamic parameters (H
d = 22 kJ mol–1; S
d = –0.29 kJ mol–1 K–1). This last phenomenon proved particularly slow for the system under consideration, probably because the biocatalyst link to the mycelium was able to improve its thermostability. In view of future continuous application, the effects of operating time, starting substrate concentration and temperature on the theoretical integral productivity of a fixed-bed column filled with this biocatalyst have been investigated. 相似文献
17.
Generation of transgenic wheat (Triticum aestivum L.) for constitutive accumulation of an Aspergillus phytase 总被引:6,自引:0,他引:6
Brinch-Pedersen Henrik Olesen Annette Rasmussen Søren K. Holm Preben B. 《Molecular breeding : new strategies in plant improvement》2000,6(2):195-206
The Aspergillus niger phytase-encoding gene (phyA) has been constitutively expressed in wheat. Transgenic wheat lines were generated by microprojectile bombardment of immature embryos, using the bar-Bialaphos selection system. The bar and the phyA gene expression were controlled by the maize ubiquitin-1 promoter. To ensure secretion and glycosylation of the microbial phytase, an expression cassette was designed (Ubi-SP-Phy) where an -amylase signal peptide sequence was inserted between the promoter and the phytase coding region. A similar cassette was constructed without the signal peptide sequence (Ubi-Phy). Five lines of fertile wheat transformed with the Ubi-SP-Phy were generated and two lines with the Ubi-Phy construct. The inheritance of the phyA gene was monitored through three generations. Western blotting of leaf and seed derived protein revealed the presence of an immunoreacting polypeptide of the size expected for the Aspergillus phytase. Up to 25 days after pollination, the heterologous phytase was exclusively present in the pericarp-seed coat-aleurone fraction. Thereafter, it accumulated in the endosperm in amounts exceeding that found in the seed coat and aleurone. The phyA mRNA and derived protein could at no stage be detected in the embryo. The Ubi-SP-Phy transgenic seeds exhibited up to 4-fold increase of phytase activity while up to 56% increase was found in Ubi-Phy plants. It is concluded that a functional Aspergillus phytase can be produced in significant amounts in wheat grains. This may be of relevance for improving the phytate-phosphorus digestibility when wheat grains are used for non-ruminant animal feed. 相似文献
18.
Tamalampudi S Talukder MM Hama S Tanino T Suzuki Y Kondo A Fukuda H 《Applied microbiology and biotechnology》2007,75(2):387-395
To expand the industrial applications of Candida antarctica lipase B (CALB), we developed Aspergillus oryzae whole-cell biocatalyst expressing the lipase-encoding gene from C. antarctica. A. oryzae niaD300, which was derived from the wild type strain RIB40, was used as the host strain. The CALB gene was isolated from
C. antarctica CBS6678 and expression plasmids were constructed with and without secretion signal peptide. The lipase gene was expressed
under the control of improved glaA and pNo-8142 promoters of plasmids pNGA142 and pNAN8142, respectively. The Southern blot
analysis demonstrated the successful integration of the CALB gene in the genome of A. oryzae. To determine the role of signal peptide, the expression plasmids were constructed with homologous and heterologous secretion
signal sequences of triacylglycerol lipase gene (tglA) from A. oryzae and lipase B (CALB) from C. antarctica, respectively. The C-terminal FLAG tag does not alter the catalytic properties of the lipase enzyme and Western blotting
analysis using anti-FLAG antibodies demonstrated the presence of cell wall and membrane bound lipase responsible for the biocatalytic
activity of the whole-cell biocatalyst. The resultant recombinant A. oryzae was immobilized within biomass support particles (BSPs) made of polyurethane foam (PUF) and the BSPs were successfully used
for the hydrolysis of para-nitrophenol butyrate (p-NPB) and for the optical resolution of (RS)-1-phenyl ethanol by enantioselective transesterification with vinyl acetate as acyl donor. 相似文献
19.
Sapna 《Biocatalysis and Biotransformation》2015,33(3):167-174
Production of protease-resistant phytase by Aspergillus oryzae SBS50 was optimized in solid state fermentation using wheat bran as substrate. An integrated statistical optimization approach involving the Placket–Burman design followed by response surface methodology was employed. Among all the variables tested, incubation period, triton X-100, moisture ratio, and magnesium sulphate were identified as significant and further optimized using response surface methodology that resulted in 3.35-fold improvement in phytase production from 55.43 to 185.75 U/g dry mouldy bran (DMB). Optimal conditions for maximum phytase production (185.75 U/g DMB) included wheat bran 10 g per 250 ml flask moistened with 35 ml distilled water supplemented with 3.0% triton X-100, 0.04% magnesium sulphate, 1.0% sucrose and 0.5% yeast extract incubated at 30?°C for an incubation time of 48 h. Phytase titers were sustainable (179.55 to 185.75 U/g DMB), when the mould was grown in shake flasks of varied volumes and enamel-coated metallic trays under optimized conditions. Fermentation time was reduced to half from 96 h to 48 h after optimization resulting in a 6.7-fold enhancement in the phytase productivity from 577.39 to 3868.75 U/Kg/h and thus, reducing the cost of enzyme production. Phytase released inorganic phosphate, reducing sugars and soluble proteins from different food samples in a time dependent manner as a result of phytate hydrolysis. 相似文献
20.
Ineke E. Mattern Shiela Unkles Jim R. Kinghorn Peter H. Pouwels Cees A. M. J. J. van den Hondel 《Molecular & general genetics : MGG》1987,210(3):460-461
Summary A transformation system for Aspergillus oryzae based on the orotidine-5-phosphate decarboxylase gene (pyrG) was developed. Transformation frequencies of up to 16 transformants per g of DNA were obtained with the vector pAB4-1, which carries the pyrG gene of A. niger. Southern blotting analysis showed that vector DNA sequences were integrated into the chromosomal DNA, in various copy numbers and presumably at different sites. Efficient cotransformation of an unselectable gene was also shown. Under the conditions used no transformants were obtained with the equivalent pyr4 gene of Neurospora crassa. 相似文献