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1.
Change in the oxidation state of manganese atoms in unbleached hardwood kraft pulp (UKP) during the biological bleaching of UKP with Phanerochaete sordida YK-624 was determined by the electron spin resonance (ESR) method. The spectrum of Mn(II), which reveals hyperfine splitting, was not observed in the ESR analysis of UKP, but the spectrum for manganese dioxide was observed. After fungal treatment of UKP with P. sordida YK-624, the spectrum of Mn(II) was detected. The reduction of manganese dioxide was triggered by the increase in NADPH-dependent ferrireductase activity. It is concluded that the manganese dioxide dominant in UKP was reduced by P. sordida YK-624 to Mn(II), which stimulates the production and function of manganese peroxidase. 相似文献
2.
Reduction of manganese dioxide is demonstrated for an in vitro ferrireductase system that includes NADPH-dependent ferrireductase and the iron-binding compound (IBC) isolated from the white-rot fungus Phanerochaete sordida YK-624. The Fe(II)–IBC complex was more effective in reducing manganese dioxide to Mn(II) than were complexes of Fe(II) and organic acids of low molecular weight such as nitrilotriacetate, although IBC also reduced manganese dioxide to Mn(II) in the absence of Fe(II). The generated Fe(III)–IBC complex was a better substrate for NADPH-dependent ferrireductase than were other ferric chelates, suggesting that the Fe(III)–IBC complex is reduced to an Fe(II) complex by NADPH-dependent ferrireductase. Moreover, production of the Fe(III)–IBC complex by the reduction of manganese dioxide in a reaction system containing Fe(II) and IBC was observed to be coupled to reduction of the Fe(III)–IBC complex by NADPH-dependent ferrireductase. These results indicate that the ferrireductase system of P. sordida YK-624 plays an important role in the reduction of manganese dioxide, which is necessary for the production and function of manganese peroxidase. 相似文献
3.
Iron-binding compounds were isolated from a culture of Phanerochaete sordida YK-624 and were found to bind to Fe(III) preferentially compared with Fe(II). Two iron-binding compounds were purified to near-homogeneity with gel permeation chromatography. Hydrolysis of the iron-binding compounds with 6N hydrochloric acid gave ninhydrin-negative products. The molecular weight of these compounds was 3–5 kDa. These compounds may play an important role in the reduction of extracellular manganese dioxide to Mn(II) by intracellular ferrireductases for lignin degradation by manganese peroxidase. 相似文献
4.
An intracellular, soluble ferrireductase thought to be involved in the reduction of manganese dioxide by white-rot fungus Phanerochaete sordida YK-624 was purified for the first time. Two isoenzymes, NAD(P)H-dependent and NADPH-dependent, respectively, were detected by hydrophobic chromatography. The NADPH-dependent ferrireductase was purified to homogeneity by ammonium sulfate fractionation, hydrophobic interaction, gel permeation, and anion-exchange chromatography. The purified protein, which is monomeric, has a molecular mass of 35 kDa (determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis) and pl 5.1 (determined by isoelectric focusing). The purified protein did not use cellobiose as an electron donor. The purified protein reduced Fe(III)-nitrilotriacetate complex, Mn(III)-malonate complex, methoxy- p-benzoquinone, and cytochrome c; veratraldehyde, 2-hydroxy-1,4-naphthoquinone, phenazine methosulfate, and plumbagin could not be reduced. Particularly, the protein showed the highest reducing rate for Fe(III)-organic acid complexes, such as Fe(III)-nitrilotriacetate, among these electron acceptors. 相似文献
5.
本文对8种木腐菌,13株菌株的木质素分解酶活力进行了初步研究,结果表明:13株木腐菌菌株都具有程度不同的木质素分解酶活力,其中白腐菌的木质素分解酶活力高于褐腐菌,酶活力增长速度较快,高酶活力维持时间长。这些结果对于木材防腐研究及白腐菌综合利用的研究具有一定的参考价值。 相似文献
6.
The relationship between the taxa of airborne fungi and the decay risk was investigated. Airborne fungi in 1,000 l of air
were trapped on Japanese cedar disks, and incubated in a damp container kept at 26oC. After 16-week incubation, filamentous
fungi grown on the disks were isolated and DNA extracted from each isolate was amplified with the primers ITS4/ITS5. The DNA
sequences of the amplified products were determined and compared to the sequence data of GenBank to determine the species
or genus according to a BLAST search. This search revealed that the isolate consisted of 5 major taxa, namely Bjerkandera sp., Phanerochaete sp. (A), Phanerochaete sp. (B), Polyporales sp. Polyporus arcularius, and 6 minor ones. Statistical analysis revealed that the major taxa were trapped on the disks in similar weather conditions
except for Bjerkandera sp., which was trapped at a cooler temperature. The analysis also proved the disks to which Phanerochaete spp. or Polyporales sp. were attached showed higher mass loss. It is concluded that, under these experimental conditions, related species of
Phanerochaete sordida play an important role in increasing the decay risk caused by airborne wood-decay fungi. 相似文献
7.
The natural resistance of Erythrophleum fordii Oliver wood to degradation by Phanerochaete sordida and Phanerochaete chrysosporium white-rot fungi was investigated. In this study, Fagus crenata Blume (Japanese beech) was selected as reference species. The results showed that both fungi caused less than 2% mass loss in E. fordii wood, while the degradation of beech wood produced by P. chrysosporium and P. sordida was approximately 12 and 14%, respectively. Microscopic observations revealed high structural rigidity of E. fordii timber. Hyphae were only observed in the lumen of vessels and parenchymal cells, while the fibers were not affected. The E. fordii wood fiber consisted of highly lignified thick-walled fibers with the fiber lumina almost completely closed. Two-dimensional heteronuclear single-quantum coherence nuclear magnetic resonance evaluation revealed the E. fordii wood to have a highly condensed-lignin structure that reflected by the durability classes. These unique parameters are likely to be critical for the high natural resistance of E. fordii. 相似文献
8.
Six months after planting, seedlings of the leguminous tree Dalbergia nigra, known as Brazilian rosewood, wereinoculated with a selected Bradyrhizobium strainBHICB-DN 15,either alone or in combination with mycorrhizal fungi to determine their effecton the growth of D. nigra in Atlantic forest andeucalyptussoils. Height growth of D. nigra was similar in both soilsand six months after inoculation Bradyrhizobium did notaffect the D. nigra height growth, but it did improve drymass and especially in the nitrogen content of plants grown in eucalyptus soil.The success of the delayed inoculation with BHICB-DN 15 confirms its competitiveability vis-à-vis indigenous soil rhizobia. Co-inoculationof BHICB-DN 15 and mycorrhizal fungi did not increase plant dry weight,nitrogenand phosphorus content or mycorrhizal colonization. These results suggest thatthe BHICB-DN 15 strain had no synergistic relationship with the mycorrhizalfungi or that there was incompatibility between symbionts, in both soils. 相似文献
9.
The association between blue stain fungi and Ips cembrae Heer (Coleoptera: Scolytidae) was investigated in the Japanese larch, Larix leptolepis Gordon, in the Nagoya University Forest, Aichi Prefecture, central Japan. I. cembrae had one or two generation(s) in a year in this study area. Two blue stain fungi, Ophiostoma piceae and Leptographium sp., were isolated from the body surface of both male adults in mating chambers and female adults in parent galleries, suggesting
that this beetle species was a vector of these fungi. Although no blue stain fungi were isolated from non-stained wood, both
fungi were isolated from the mating chambers, the center and the uppermost end of the galleries throughout the season. The
fact that O. piceae was consistently isolated with high frequency from adults and from their galleries strongly suggested that this species would
be the principal blue stain fungus infecting the beetle-attacked larch trees. 相似文献
10.
The effect of three levels of fertilizer on thegrowth of three species of containerized-grownconifer seedlings ( Pinus contorta, Picea glauca, and Picea mariana) and twospecies of bare-root conifer seedlings ( Pinus sylvestris and Larix sibirica),and on the colonization of these seedlings bysix species of ectomycorrhizal fungi ( Hebeloma longicaudum, Laccaria bicolor, Paxillus involutus, Pisolithustinctorius, Rhizopogon vinicolor and Suillus tomentosus), was studied. Thegrowth of the seedlings in both container-grownand bare-root nurseries increased as the levelsof fertilizer increased. For better seedlinggrowth and environmental quality it may be possible to reduce the level of fertilizers in commercial nurseries upto 33% by using selected mycorrhizal fungi.Ectomycorrhizal colonization in all seedlingswas not affected by fertilizer levels. Hebeloma longicaudum, L. bicolor, P.involutus, and P. tinctorius formedwell-developed ectomycorrhizae, whereasectomycorrhizal development by R.vinicolor and S. tomentosus was poor.Native mycorrhizal fungi colonizednon-inoculated control seedlings; however,their colonization was always lower than withinoculated fungi. 相似文献
12.
In this study, the decay resistance of untreated and thermally modified jack pine (Pinus Banksiana), aspen ( Populus tremuloides), and white birch ( Betula Papyrifera) was evaluated. Wood specimens were exposed to laboratory decay resistance tests using the wood-rot fungi, Trametes. versicolor, Poria placenta, and Gloephyllum trabeum for 2–12 weeks of incubation. The results indicated that, T. versicolor fungus was virulent against all the three untreated woods, B. papyrifera (73.9% weight loss), P. tremuloides (57.1% weight loss), and P. banksiana (43.5% weight loss). P. placenta fungus affected B. papyrifera (52.4% weight loss), P. banksiana (52.3% weight loss), and P. tremuloides (36.7% weight loss). G. trabeum fungus was virulent against P. banksiana (41.53% weight loss), but less active against B. papyrifera (11.6% weight loss) and P. tremuloides (21.9% weight loss). It was found that the weight losses due to T. versicolor fungus activity were reduced for P. banksiana (1.5% weight loss) thermally modified at 210 °C, B. papyrifera (27.9% weight loss) at 215 °C, and P. tremuloides (9% weight loss) at 220 °C compared to the weight losses of their untreated counterparts. These correspond to 96.5%, 62.2% and 84.2% of decrease in weight loss, respectively. Similar results were obtained with G. trabeum fungus. On the contrary, thermal modification on the deterioration of P. banksiana (39.1% weight loss) by P. Placenta was affected less resulting in only 25.2% weight loss relative to untreated wood. 相似文献
13.
利用木素特有的紫外吸收波长,通过定量测定含木素溶液中酶作用前后木素物质(底物)的变化量,测定本腐菌本素分解酶的活力,具有操作步骤简单、测定速度快等优点,为高木素代谢能力菌株的筛选研究,提供了一个较好的测试方法。 相似文献
14.
Degradation of high-molecular-weight polyethylene membrane by lignin-degrading fungi, IZU-154, Phanerochaete chrysosporium, and Trametes versicolor, was investigated under various nutritional conditions. IZU-154 showed the most significant polyethylene degradation among the three lignin-degrading fungi under nitrogen- or carbon-limited culture conditions. Furthermore, for T. versicolor and P. chrysosporium, the addition of Mn(II) into nitrogen- or carbon-limited culture medium enhanced polyethylene degradation. These results suggest that polyethylene degradation is related to ligninolytic activity of lignin-degrading fungi. Treatment of polyethylene membrane with partially purified manganese peroxidase (MnP) caused significant degradation in the presence of Tween 80, Mn(II), and Mn(III) chelator. This result demonstrates that MnP is the key enzyme in polyethylene degradation by lignin-degrading fungi.This study was presented in part at the 9th International Symposium on Wood and Pulping Chemistry, Montreal, Canada, June 9–12, 1997 相似文献
15.
Examples are given of North American fungi potentially dangerous to Pinus contorta plantations in northern Europe. The pathogenicity of North European fungi is discussed. P. contorta was found to be immune or nearly immune to all European rust fungi, more resistant than P. sylvestris to Phacidium infestans and Lophodermium pinastri, but less resistant to Crumenulopsis sororia and Discella strobilina. For other fungi no such clearcut conclusions could be drawn. 相似文献
16.
A number of various species of blue-stain fungi were isolated from Tomicus piniperda adults at various stages of development, as well as from the galleries, pupal chambers and sapwood underneath galleries on
Japanese red pine. This study was an attempt to identify the species, composition of blue-stain fungi associated with T. piniperda, the frequency of occurrence of the fungi, and their role in the sapwood-staining of Japanese red pine in Tsukuba City, central
Japan. Among the seven species of blue-stain fungi isolated, an undescribed species of Ophiostoma together with O. minus were the dominant species and closely associated with T. piniperda. These two species occurred on newly emerging adults more frequently than the overwintered adults. Hormonema dematioides was also associated with the beetle, however, its frequency of occurrence from the emerged new adults was very low. Although
the two other species, O. ips and Graphium sp. were also isolated from emerged beetles, the frequency of these fungi from gallery systems suggested that they were accidentally
carried by T. piniperda. Leptographium wingfieldii, known to be associated with the beetle in Europe, was also isolated at a very low frequency and the fungus seemed not to
be closely associated with the beetle. Ophiostoma sp. and O. minus appear to be the most important causes of blue-stain of Japanese red pine sapwood after infestation by T. piniperda. 相似文献
17.
Paulownia tomentosa, P. fargesii, P. lamprorhylla, P. albiphloea, P. australis, P. fortunei, P. elongata, P. elongata f. alba and P. albiphloea var chenggtuensis were classified into three groups: P. fortunei group ( P. fortunei and P. elongata f. alba); P. australis group ( P. australis and P. albiphloea var chenggtuensis) and P. tomentasa group ( P. tomentasa, P. fargesii, P. albiprhlaca, P. lamproprhylia and P. elongata) accordance to the results of the single and two-dimensional SDS-PAGE of protein in the Paulownia tree leaves. The result could lay a foundation for classifying the Genus Paulownia plants.
Foundation Item: This paper was supported by National Nature Science Foundation of China and Nature Science Foundation of Henan Province.
Biography: FAN Guo-qiang (1964-), male, Professor in Institute of Paulownia Henan Agriculture University. Zhengzhou 450002, P. R. China.
Responsible editor: Song Funan 相似文献
18.
Yezo spruce trees ( Picea jezoensis), approximately 40-year-old were inoculated with eight ophiostomatoid fungi associated with Ips typographus f. japonicus to compare relative virulence of the fungi. Among them, Ophistoma penicillatum formed the longest necrotic lesion on inner bark around inoculation points, followed by O. aenigmaticum, Ceratocystis polonica, and O. bicolor, while C. polonica formed a larger dry zone in sapwood than the other fungi. Yezo spruce trees were also mass inoculated with C. polonica, O. penicillatum, O. piceae singly or mixed to demonstrate the ability of the fungi to kill Yezo spruce trees. The trees inoculated with C. polonica, O. penicillatum or the mixed inoculum showed discoloration of needles in the early summer of the next year and died by autumn. However, the
trees inoculated with O. piceae or the control inocula did not die, except for one tree. These results indicated that C. polonica and O. penicillatum were more virulent than O. piceae and suggested that they might be at least partially responsible for the mortality of the beetle-infested Yezo spruce trees.
Part of this study was supported by the Sumitomo Foundation, Japan to Y. Yamaoka and I. Takahashi.
Part of this study was presented at the 107th meeting of the Japanese Forestry Society, April 1–4, 1996, Tsukuba, Ibaraki,
at the 42nd annual meeting of the Mycological Society of Japan, May 16–17, 1998, Kyoto, and at the 110th meeting of the Japanese
Forestry Society, April 2–5, 1999, Matsuyama, Ehime.
Contribution No. 143, Laboratories of Plant Pathology and Mycology, Institute of Agriculture and Forestry, University of Tsukuba. 相似文献
19.
Applicability of gaseous treatment with allyl isothiocyanate (AIT) was evaluated for controlling the established microbial infestation of wood in the laboratory. Small sapwood specimens from five wood species measuring 20 mm (T)×20 mm (R)×10 mm (L) were first preincubated on 2% malt-agar medium with placing them on a fully grown monoculture of seven test fungi. After 7 weeks of preincubation they were transferred to fresh medium and exposed to AIT fumigant at concentrations of 2360 and 23600ppm AIT in the air of a petri dish to determine threshold values of exposure periods for each test fungus. The 2360 ppm concentration was not effective for Penicillium funiculosum, Gliocladium virens, or Rhizopus stolonifer for any of the wood species-exposure period combinations. Those test fungi could grow even at 23600ppm after 48h exposure when Cryptomeria japonica and Fagus crenata were used as wood substrate. Growth of other test fungi was inhibited at 2360ppm with a few exceptions in the case of Aspergillus niger. The required periods of exposure to suppress microbial regrowth were different with wood species-test fungi combinations. As two wood-decaying basidiomycetes, Trametes versicolor and Fomitopsis palustris, were easily controlled at 2360ppm after 24h exposure regardless of wood species, AIT treatment proved applicable to the control of internal decay of utility poles and other relevant products in service. 相似文献
20.
We have isolated the cDNA and genomic sequences encoding the major isozyme of manganese peroxidase, MnP3, from the white rot basidiomycete Pleurotus ostreatus strain IS1. The gene mnp3 is interrupted by 10 introns and encodes a mature protein of 357 amino acid residues with a 26-amino-acid signal peptide. The amino acid residues known to be involved in peroxidase function and those that form the Mn-binding site in the Panerochaete chrysosporium MnP isozyme are conserved in MnP3. Comparison of the deduced primary structure of MnP3 with those of other peroxidases from various white rot fungi suggested that MnPs from P. ostreatus and Trametes versicolor belong to a subgroup that is more similar to the lignin peroxidases than MnPs from P. chrysosporium or Ceriporiopsis subvermispora. 相似文献
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