共查询到20条相似文献,搜索用时 15 毫秒
1.
Naomi Miyake Yuki Masuda Yukihito Murata Munechika Inoue Ken Matuda Kousaku Okamoto Hiroaki Nanba Noriko Kodama 《Mycoscience》2006,47(2):78-83
We previously reported that MD-Fraction (Klasma-MD), a specific-structured β-glucan extracted from fruit bodies of maitake
mushrooms (Grifola frondosa), can activate cellular immune systems and express antitumor effects. The molecular weight of the MD-Fraction ranged from
1 200 000 to 2 000 000. The molecular weight of the products of the MD-Fraction obtained after hydrolysis by endo-β-1,6-glucanase
from Tricoderma harzianum was reduced to 250 000 in terms of dextran, and these products inhibited MM-46 carcinoma in C3H/HeJ mice by 67.9% after intraperitoneal
injection. In addition, interleukin-12 and interferon-γ values were increased 1.4 fold and 2.1 fold, respectively, compared
with control values. From these results, low molecular weight MD-Fraction (L-MD-Fraction) maintains an immunological active
site. 相似文献
2.
A new screening method for β-(1,3–1,6) glucan hydrolase was developed using a pure β-glucan from Aureobaisidum pullulans by zymography and an LB-agar plate. Paenibacillus sp. was screened as a producer a β-glucan hydrolase on the Trypan Blue-coupled β-glucan LB-agar plate and the activity of
the enzyme was analyzed by SDS-β-glucan zymography. The β-glucan was not hydrolyzed by Bacillus spp. strains, which exhibit cellulolytic activity on CMC zymography. The gene, obtaining by shotgun cloning and encoding
the β-glucan hydrolase of Paenibacillus sp. was sequenced. 相似文献
3.
Kawai R Igarashi K Yoshida M Kitaoka M Samejima M 《Applied microbiology and biotechnology》2006,71(6):898-906
When Phanerochaete chrysosporium was grown with laminarin (a β-1,3/1,6-glucan) as the sole carbon source, a β-1,3-glucanase with a molecular mass of 36 kDa was produced as a major extracellular protein. The cDNA encoding this enzyme was cloned, and the deduced amino acid sequence revealed that this enzyme belongs to glycoside hydrolase family 16; it was named Lam16A. Recombinant Lam16A, expressed in the methylotrophic yeast Pichia pastoris, randomly hydrolyzes linear β-1,3-glucan, branched β-1,3/1,6-glucan, and β-1,3-1,4-glucan, suggesting that the enzyme is a typical endo-1,3(4)-β-glucanase (EC 3.2.1.6) with broad substrate specificity for β-1,3-glucans. When laminarin and lichenan were used as substrates, Lam16A produced 6-O-glucosyl-laminaritriose (β-d-Glcp-(1–>6)-β-d-Glcp-(1–>3)-β-d-Glcp-(1–>3)-d-Glc) and 4-O-glucosyl-laminaribiose (β-d-Glcp-(1–>4)-β-d-Glcp-(1–>3)-d-Glc), respectively, as one of the major products. These results suggested that the enzyme strictly recognizes β-d-Glcp-(1–>3)-d-Glcp at subsites −2 and −1, whereas it permits 6-O-glucosyl substitution at subsite +1 and a β-1,4-glucosidic linkage at the catalytic site. Consequently, Lam16A generates non-branched oligosaccharide from branched β-1,3/1,6-glucan and, thus, may contribute to the effective degradation of such molecules in combination with other extracellular β-1,3-glucanases. 相似文献
4.
The basidiomycete Phanerochaete chrysosporium produces several β-1,3-glucanases when grown on laminarin, a β-1,3/1,6-glucan, as the sole carbon source. To characterize
one of the major unknown β-1, 3-glucanases with a molecular mass of 83 kDa, identification, cloning, and heterologous over-expression
were carried out using the total genomic information of P. chrysosporium. The cDNA encoding this enzyme included an ORF of 2337 bp and the deduced amino acid sequence contains a predicted signal
peptide of 26 amino acids and the mature protein of 752 amino acids. The amino acid sequence showed a significant similarity
with glycoside hydrolase family 55 enzymes from filamentous fungi and was named Lam55A. Since the recombinant Lam55A expressed
in the methylotrophic yeast Pichia pastoris degraded branched β-1,3/1,6-glucan as well as linear β-1,3-glucan, the kinetic features of the enzyme were compared with
those of other β-1,3-glucanases. 相似文献
5.
Immune response to liver-specific lipoprotein (LSP) is involved in the pathogenesis of chronic active hepatitis. Experimental
hepatitis could thus be prepared in C57BL/6 mice by injection of liver-specific protein in a syngeneic liver homogenate with
Freund's complete adjuvant. In hepatitic mice treated with maitake (Grifola frondosa) fruit bodies, the values of glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) values increased
temporarily by 2.24–2.79 times and decreased rapidly thereafter. However, in the mice given normal feed, both values increased
constantly. Thus, we examined T cell activities both in the exacerbation and remission stages of hepatitis. We suggest that
the activation of CD8+ cells is more potentiated than that of CD4+ cells by administration of maitake or the D-Fraction-glucan (β-1,6 glucan having β-1,3 branches), which can enhance immuno-competent
cells at the exacerbation stage. However, at the remission stage, marked potentiation of CD8+ cell activity was not observed. These results suggest that depressed suppressor T cell activity is revived by the X-Fraction-glucan
(β-1,6 glucan having α-1,4 branched glucan), while the cytotoxic T cell activity, which is activated by the D-Fraction, is
restricted, thereby creating a smooth shift from the exacerbation stage to the remission stage. 相似文献
6.
Rebecca Schimoler-O'Rourke Samantha Renault Wenjun Mo Claude P. Selitrennikoff 《Current microbiology》2003,46(6):0408-0412
The essential fungal cell-wall polymer (1,3)β-glucan is synthesized by the enzyme (1,3)β-glucan synthase. This enzyme, which
is the target of the echinocandin and pneumocandin families of fungicidal antibiotics, is a complex composed of at least two
proteins, Rho1p and Fks1p. Homologs of the yeast FKS1 gene have been discovered in numerous fungi, and existing evidence points to, but has not yet proved, Fks1p being the catalytic
subunit of (1,3)β-glucan synthase. We have purified (1,3)β-glucan synthase from Neurospora crassa ∼400-fold enrichment and labeled the substrate-binding protein by using a UDP-glucose analog, 5-azido-[β-32P]-UDP-glucose. UDP-glucose-binding proteins were photo-crosslinked to the substrate analog and identified from SDS-PAGE gels
by Quadrupole time-of-flight mass spectrometry by sequencing the tryptic peptides. Two plasma membrane proteins were labeled
FKS and H+-ATPase. These results suggest that FKS appears to be the substrate-binding subunit of (1,3)β-glucan synthase.
Received: 31 May 2002 / Accepted: 27 July 2002 相似文献
7.
Maitake D-Fraction is a polysaccharide extracted from the maitake mushroom (Grifola frondosa S.F. Gray). It is a β-glucan with a β-1,6 main chain with β-1,3 branches. Using normal C3H/Hej mice, its effects on the natural
immune system, including macrophages, dendritic cells, and natural killer (NK) cells, were investigated. NK cells attack cells
infected with pathogens such as bacteria and virus and produce cytokines, such as interferon-gamma (IFN-γ), that can modulate
natural and specific immune responses. D-Fraction was administered to the mice intraperitoneally for 3 consecutive days; spleen
cells containing macrophages and dendritic cells were then cultured and the culture supernatants were analyzed for IL-12.
At the same time, IFN-γ expression in splenic NK cells was investigated. The levels of these cytokines were increased by D-Fraction.
To elucidate NK cell activation by D-Fraction, CD69 expression on the surface of activated NK cells was examined, resulting
in an increase in CD69-positive ratio for splenic NK cells. These results indicate that D-Fraction stimulates the natural
immunity related to the activation of NK cells indirectly through IL-12 produced by macrophages and dendritic cells. Therefore,
administration of D-Fraction to healthy individuals may serve to prevent infection.
Received: August 1, 2002 / Accepted: February 10, 2003 相似文献
8.
Two exo-β-glucanases (LP-ExoI, 83 kDa and LP-ExoII, 71 kDa) were extracted and partially purified from the cell wall of Lilium longiflorum pollen tubes. Both LP-ExoI and LP-ExoII hydrolyzed laminarin (1,3-β-glucan). These enzymes also exhibited some activity toward
1,3:1,4-β-glucans of Hordeum vulgare and Cetraria islandica and the 1,6-β-glucan of Umbilicaria papullosa. The pH for optimum activity for both exo-β-glucanases was 5.5. Methylation analysis of the reaction products revealed that
purified LP-ExoI decreased both 1,3- and 1,4-glucosyl linkages in hemicellulosic polysaccharides isolated from the cell wall
of lily pollen tubes. D-gluconolactone and nojirimycin, inhibitors of glucosidase, inhibited activities of both exo-β-glucanases,
as well as growth of the lily pollen tubes. These results disclosed that the wall-bound exo-β-glucanases play an important
role in the regulation of lily pollen tube growth.
Received: 3 January 2000 / Revision accepted: 8 March 2000 相似文献
9.
10.
Minoru Ujita Yosuke Katsuno Kahori Suzuki Kazumasa Sugiyama Eiji Takeda Eiji Yokoyama Akira Hara 《Mycoscience》2006,47(2):98-105
The entomopathogenic fungus Cordyceps militaris belongs to vegetable wasps and plant worms and is used as herbal medicine, but β-1,3-glucan biosynthesis has been poorly
studied in C. militaris. The fungal FKS1 gene encodes an integral membrane protein that is the catalytic subunit of β-1,3-glucan synthase. Here, we isolated cDNA
clones encoding a full-length open reading frame of C. militaris FKS1. Cordyceps militaris Fks1 protein is a 1981 amino acid protein that shows significant similarity with other fungal Fks proteins. This study is
the first report of molecular cloning of the β-1,3-glucan synthase catalytic subunit gene from vegetable wasps and plant worms. 相似文献
11.
12.
S. Tentler J. Palas C. Enderlin J. Campbell C. Taft T.K. Miller R.L. Wood C.P. Selitrennikoff 《Current microbiology》1997,34(5):303-308
We have used the filamentous fungus, Neurospora
crassa, as a model system to test the concept that antisense targeting of
the cell-wall assembly enzyme, (1,3)β-glucan synthase [E.C. 2.4.1.34; UDP
glucose: 1,3-β-D-glucan 3-β-D-glucosyltransferase], leads to a
corresponding decrease in growth of the organism. Previously, our laboratory
isolated a gene (glucan synthase-1, gs-1) that is required for
(1,3)β-glucan synthase activity. Wild-type cells were transformed with DNA
vectors encoding various RNAs complementary to the gs-1 messenger RNA
(antisense RNA) cloned downstream from an inducible promoter (quinic acid-2
[qa-2p]). Stable transformants, expressing a partially inverted
antisense message of gs-1 (pMYX107), exhibited dramatic reduction in
growth compared with empty vector controls. Hyphal measurements of these
transformants grown on race tubes indicated that all of the transformants
showed various degrees of inhibition. Microscopic observations of
transformants revealed shorter hyphal lengths when grown under conditions
expressing antisense. Further characterization revealed that the specific
activities of (1,3)β-glucan synthase were decreased by as much as
63% relative to empty vector controls. Together, these observations
suggest that antisense against (1,3)β-glucan synthase led to a reduction in
enzyme levels that resulted in altered cell-wall morphology and inhibition of
growth. It is possible that antisense oligonucleotides against gs-1
may be useful antifungal agents.
Received: 20 September 1996 / Accepted: 1 November 1996 相似文献
13.
Teng D Fan Y Yang YL Tian ZG Luo J Wang JH 《Applied microbiology and biotechnology》2007,74(5):1074-1083
β-1,3-1,4-glucanase (EC3.2.1.73) as an important industrial enzyme has been widely used in the brewing and animal feed additive
industry. To improve expression efficiency of recombinant β-1,3-1,4-glucanase from Bacillus licheniformis EGW039(CGMCC 0635) in methylotrophic yeast Pichia pastoris GS115, the DNA sequence encoding β-1,3-1,4-glucanase was designed and synthesized based on the codon bias of P. pastoris, the codons encoding 96 amino acids were optimized, in which a total of 102 nucleotides were changed, the G+C ratio was simultaneously
increased from 43.6 to 45.5%. At shaking flask level, β-1,3-1,4-glucanase activity is 67.9 and 52.3 U ml−1 with barley β-glucan and lichenan as substrate, respectively. At laboratory fermentor level, the secreted protein concentration
is approximately 250 mg l−1. The β-1,3-1,4-glucanase activity is 333.7 and 256.7 U ml−1 with barley β-glucan and lichenan as substrate, respectively; however, no activity of this enzyme on cellulose is observed.
Compared to the nonoptimized control, expression level of the optimized β-1,3-1,4-glucanase based on preferred codons in P. pastoris shown a 10-fold higher level. The codon-optimized enzyme was approximately 53.8% of the total secreted protein. The optimal
acidity and temperature of this recombinant enzyme were pH 6.0 and 45°C, respectively. 相似文献
14.
Huiying Luo Jun Yang Peilong Yang Jiang Li Huoqing Huang Pengjun Shi Yingguo Bai Yaru Wang Yunliu Fan Bin Yao 《Applied microbiology and biotechnology》2010,85(4):1015-1023
Most reported microbial β-1,3-1,4-glucanases belong to the glycoside hydrolase family 16. Here, we report a new acidic family
7 endo-β-1,3-1,4-glucanase (Bgl7A) from the acidophilic fungus Bispora sp. MEY-1. The cDNA of Bgl7A was isolated and over-expressed in Pichia pastoris, with a yield of about 1,000 U ml–1 in a 3.7-l fermentor. The purified recombinant Bgl7A had three activity peaks at pH 1.5, 3.5, and 5.0 (maximum), respectively,
and a temperature optimum at 60°C. The enzyme was stable at pH 1.0–8.0 and highly resistant to both pepsin and trypsin. Belonging
to the group of non-specific endoglucanase, Bgl7A can hydrolyze not only β-glucan and cellulose but also laminarin and oat
spelt xylan. The specific activity of Bgl7A against barley β-glucan and lichenan (4,040 and 2,740 U mg–1) was higher than toward carboxymethyl cellulose sodium (395 U mg–1), which was different from other family 7 endo-β-glucanases. 相似文献
15.
Sakamoto T Tanaka H Nishimura Y Ishimaru M Kasai N 《Applied microbiology and biotechnology》2011,90(5):1701-1710
A type II arabinogalactan-degrading enzyme, termed Exo-1,3-Gal, was purified to homogeneity from the culture filtrate of Sphingomonas sp. 24T. It has an apparent molecular mass of 48 kDa by SDS–PAGE. Exo-1,3-Gal was stable from pH 3 to 10 and at temperatures
up to 40 °C. The optimum pH and temperature for enzyme activity were pH 6 to 7 and 50 °C, respectively. Galactose was released
from β-1,3-d-galactan and β-1,3-d-galactooligosaccharides by the action of Exo-1,3-Gal, indicating that the enzyme was an exo-β-1,3-d-galactanase. Analysis of the reaction products of β-1,3-galactotriose by high-performance anion-exchange chromatography revealed
that the enzyme hydrolyzed the substrate in a non-processive mode. Exo-1,3-Gal bypassed the branching points of β-1,3-galactan
backbones in larch wood arabinogalactan (LWAG) to produce mainly galactose, β-1,6-galactobiose, and unidentified oligosaccharides
1 and 2 with the molar ratios of 7:19:62:12. Oligosaccharides 1 and 2 were enzymatically determined to be β-1,6-galactotriose
and β-1,6-galactotriose substituted with a single arabinofuranose residue, respectively. The ratio of side chains enzymatically
released from LWAG was in good agreement with the postulated structure of the polysaccharide previously determined by chemical
methods. 相似文献
16.
Ying Peng Zhenming Chi Xianghong Wang Jing Li 《Marine biotechnology (New York, N.Y.)》2010,12(4):479-485
The marine-derived Williopsis saturnus WC91-2 was found to produce very high killer toxin activity against the pathogenic yeast Metschnikowia bicuspidata WCY isolated from the diseased crab. It is interesting to observe that the purified β-1,3-glucanase from W. saturnus WC91-2 had no killer toxin activity but could inhibit activity of the WC91-2 toxin produced by the same yeast. In contrast,
the WC91-2 toxin produced had no β-1,3-glucanase activity. We found that the mechanisms of the inhibition may be that the
β-1,3-glucanase competed for binding to β-1,3-glucan on the sensitive yeast cell wall with the WC91-2 toxin, causing decrease
in the amount of the WC91-2 toxin bound to β-1,3-glucan on the sensitive yeast cell wall and the activity of the WC91-2 toxin
against the sensitive yeast cells. In order to make W. saturnus WC91-2 produce high activity of the WC91-2 toxin against the yeast disease in crab, it is necessary to delete the gene encoding
β-1,3-glucanase. 相似文献
17.
The cell wall of Candida albicans is composed of mannoproteins associated to glycan polymers. Most of these proteins are retained in this compartment through
a phosphodiester linkage between a remnant of their glycosylphosphatidylinositol anchor and the β-1,6-glucan polymer. A pure
β-1,6-glucanase is thus required in order to release them. In this paper, we report the expression/secretion by the yeast
Yarrowia lipolytica of an Aspergillus fumigatus enzyme homologous to previously described β-1,6-glucanases. The coding sequence was expressed under the control of a strong
promoter and the recombinant enzyme was targeted to the secretory pathway using the signal sequence of a well-known major
secretory protein in this host. Addition of a FLAG epitope at the C-terminus allowed its efficient purification from culture
supernatant following batch adsorption. The purified enzyme was characterized as a β-1,6-glucanase and was shown to be active
on C. albicans cell walls allowing the release of a previously described cell wall protein. 相似文献
18.
Nakajima M Yamashita T Takahashi M Nakano Y Takeda T 《Applied microbiology and biotechnology》2012,93(5):1989-1998
Hydrolytic enzymes responsible for laminarin degradation were found to be secreted during growth of Ustilago esculenta on laminarin. An enzyme involved in laminarin degradation was purified by assaying release of glucose from laminaribiose.
Ion-exchange chromatography of the culture filtrate followed by size-exclusion chromatography yielded a 110-kDa protein associated
with laminaribiose hydrolysis. LC/MS/MS analysis of the 110-kDa protein identified three peptide sequences that shared significant
similarity with a putative glucoside hydrolase family (GH) 3 β-glucosidase in Ustilago maydis. Based on the DNA sequence of the U. maydis GH3 β-glucosidase, a gene encoding a putative GH3 β-glucosidase in U. esculenta (Uebgl3A) was cloned by PCR. Based on the deduced amino acid sequence, the protein encoded by Uebgl3A has a molecular mass of 91 kDa and shares 90% identity with U. maydis GH3 β-glucosidase. Recombinant UeBgl3A expressed in Aspergillus oryzae released glucose from β-1,3-, β-1,4-, and β-1,6-linked oligosaccharides, and from 1,3-1,4-β-glucan and laminarin polysaccharides,
indicating that UeBgl3A is a β-glucosidase. Kinetic analysis showed that UeBgl3A preferentially hydrolyzed laminaritriose
and laminaritetraose. These results suggest that UeBgl3A is a key enzyme that produces glucose from laminarioligosaccharides
during growth of U. esculenta on laminarin. 相似文献
19.
Abstract The cell wall of Candida albicans contains mannoproteins that are covalently associated with β-1,6-glucan. When spheroplasts were allowed to regenerate a new cell wall, initially non-glucosylated cell wall proteins accumulated in the medium. While the spheroplasts became osmotically stable, β-1,6-glucosylated proteins could be identified in their cell wall by SDS-extraction or β-1,3-glucanase digestion. At later stages of regeneration, β-1,3-glucosylated proteins were also found. Hence, incorporation of proteins into the cell wall is accompanied by extracellular coupling to β-1,6-/β-l,3-glucan. The SDS-extractable glucosylated proteins probably represent degradation products of wall proteins rather than their precursors. Tunicamycin delayed, but did not prevent the formation of β-1,6-glucosylated proteins, demonstrating that β-1,6-glucan is not attached to N -glycosidic side-chains of wall proteins. 相似文献
20.
β-Glucosidases designated MoCel3A and MoCel3B were successfully overexpressed in Magnaporthe oryzae. MoCel3A and MoCel3B showed optimal activity at 50 °C and pH 5.0–5.5. MoCel3A exhibited higher activity on higher degree of
polymerization (DP) oligosaccharides and on β-1,3-linked oligosaccharides than on β-1,4-linked oligosaccharides. Furthermore,
MoCel3A could liberate glucose from polysaccharides such as laminarin, 1,3-1,4-β-glucan, phosphoric acid-swollen cellulose,
and pustulan, of which laminarin was the most suitable substrate. Conversely, MoCel3B preferentially hydrolyzed lower DP oligosaccharides
such as cellobiose, cellotriose, and laminaribiose. Furthermore, the synergistic effects of combining enzymes including MoCel3A
and MoCel3B were investigated. Depolymerization of 1,3-1,4-β-glucan by M. oryzae cellobiohydrolase (MoCel6A) enhanced the production of glucose by the actions of MoCel3A and MoCel3B. In these reactions,
MoCel3A hydrolyzed higher DP oligosaccharides, resulting in the release of glucose and cellobiose, and MoCel3B preferentially
hydrolyzed lower DP oligosaccharides including cellobiose. On the other hand, MoCel3A alone produced glucose from laminarin
at levels equivalent to 80% of maximal hydrolysis obtained by the combined action of MoCel3A, MoCel3B, and endo-1,3-β-glucanase.
Therefore, MoCel3A and MoCel3B activities yield glucose from not only cellulosic materials but also hemicellulosic polysaccharides. 相似文献