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Postia placenta gene expression of oxidative and carbohydrate metabolism related genes during growth in furfurylated wood
2009 - IRG/WP 09-10701
A range of studies the last decade have shown that modified wood can provide excellent protection against a range of wood deteriorating organisms, including decay fungi. However, we still lack information about why the modified wood is protected from microbial attack. Several hypotheses have been put forward e.g. inhibition of action of specific enzymes, but they still need testing. An understandi...
G Alfredsen, C G Fossdal


The effects of acetylation level on the growth of Postia placenta
2011 - IRG/WP 11-10751
To understand the defence mechanisms utilized by decay fungi when exposed to different wood protection systems the study of gene expression can give us some answers. When the DNA sequences are known, primers can be designed to detect transcripts of genes with gene products related to basic cellular processes and hyphal growth. The characteristic gene products induced in different fungi by differen...
A Pilgård, G Alfredsen, C G Fossdal, C J Long II


The effects of acetylation level on the growth of Postia placenta over 36 weeks
2012 - IRG/WP 12-40589
Genomic sequencing gives us a tool to systematically and rapidly discover novel genes, how their products function in the cell, and explore their interactions. When the DNA sequences are known, primers can be designed to detect transcripts of genes with gene products related to basic cellular processes and hyphal growth. The characteristic gene products induced in different fungi by different wood...
A Pilgård, G Alfredsen, C G Fossdal, C J Long II


Effect of Trichoderma harzianum on induction of laccase by Trametes versicolor on ponderosa pine sapwood
1996 - IRG/WP 96-10177
Trichoderma harzianum has long been studied as a possible biocontrol agent against wood degrading fungi, and has provided varying degrees of protection in several European field trials. In laboratory trials, however, this fungus appears to be less active against white rot fungi. This characteristic was studied using a wood wafer sandwich procedure which simultaneously expose ponderosa pine sapwood...
E A Canessa, J J Morrell


A novel defaunation method of the protozoa to investigate cellulose metabolism in Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae)
1994 - IRG/WP 94-10050
The largest protozoa in the hindgut of workers of Formosan subterranean termite, Coptotermes formosanus Shiraki, was selectively eliminated by forced-feeding on low-molecular weight cellulose (LC) with a mean DP of 17. Although one week's feeding on LC caused perfect disappearance of Pseudotrichonympha grassii Koidzumi, the selective defaunation method itself had no detrimental effect on ...
T Yoshimura, K Tsunoda, M Takahashi


Alternative technologies for wood wastes recycling - Part B: Biotreatment of PCP- and creosote-treated wood
1998 - IRG/WP 98-50101-18 b
Alternative technologies have been investigated to detoxify treated wood. Two classes of organic compounds are studied. Creosote-treated wood are classified in France as dangerous wood wastes. A conventional incineration could be provided for these wood wastes but the cost of this elimination could be very high (> 2000 FFR/ton). For these reasons, we have tested two kinds of new processes as al...
S Legay, P Marchal, G Labat


Analysis of D-glucose metabolism of wood decay fungi using 13C-NMR and 13C-labeled substrates
2003 - IRG/WP 03-10475
D-Glucose metabolism is thought to be important during wood decay by fungi, not only for anabolic and catabolic purposes of central metabolism, but also as a potential source of peroxide required by extracellular peroxidases. There has been some confusion in the literature as to whether this peroxide-generating activity is of the glucose 1-oxidase or pyranose 2-oxidase (glucose 2-oxidase) type wi...
T H de Koker, M D Mozuch, P J Kersten


Distribution of the three symbiotic protozoa in Formosan subterranean termite, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae)
1993 - IRG/WP 93-10010
Six colonies (three each from laboratory and field) of Formosan subterranean termite, Coptotermes formosanus Shiraki, were served for investigating the abundance and distribution of three symbiotic protozoa in the hindgut of workers. The total protozoan number amounted to 6,000-10,000 per a worker, and the order of the abundance of the three protozoa and the proportional distribution of each speci...
T Yoshimura, K Tsunoda, M Takahashi


The metabolism and comparative elimination of polychlorinated biphenyl congeners in termites
1993 - IRG/WP 93-10038
Termites may serve as a potential supplementary food source for fish, poultry and pigs. Waste paper may be used as a source of food in mass rearing the termites. However, paper products and printing inks contain trace levels of toxic xenobiotics e.g. polychlorinatecl biphenyls (PCBs) and dioxins. This study examined the ability of Mastotermes darwinensis and Coptotermes acinaciformis to metabolise...
V S Haritos, J R J French, J T Ahokas


Alternative technologies for wood wastes recycling - Part A: Supercritical extraction of PAH compounds from wood wastes
1998 - IRG/WP 98-50101-18 a
Alternative technologies have been investigated to detoxify treated wood. Two classes of organic compounds are studied. Creosote-treated wood are classified in France as dangerous wood wastes. A conventional incineration could be provided for these wood wastes but the cost of this elimination could be very high (> 2000 FFR/ton). For these reasons, we have tested two kinds of new processes as al...
L Schrive, C Perre, G Labat


Oxalic acid metabolism of Postia placenta
1992 - IRG/WP 92-1566
The oxalic acid metabolism of Postia placenta was studied in liquid culture in order to identify the metabolic pathways of biosynthesis and to determine whether oxalic acid physiology could be correlated with efficiency in wood decay. Oxalic acid production was determined for test strain MAD698 grown in a basal defined medium with a variety of different carbohydrate and nitrogen sources. The highe...
J A Micales


Extracellular carbohydrate production by isolates of Postia (=Poria) placenta
1989 - IRG/WP 1388
A monokaryotic strain of Postia (=Poria) placenta, ME20, which is unable to degrade wood, also failed to produce extracellular polysaccharide when grown in liquid culture, regardless of carbon source or concentration. Other isolates of Postia placenta, including another monokaryon and a hybrid of this monokaryon with ME20, produced large quantities of this material. The polysaccharide consisted pr...
J A Micales, A L Richter, T L Highley


The effect of chitosan on the growth and physiology of two wood inhabiting fungi
2006 - IRG/WP 06-10590
The effect of chitosan on the wood inhabiting fungi Sphaeropsis sapinea and Trichoderma harzianum was evaluated at cellular level. Increasing concentrations of chitosan caused an increase in the amount of peroxide in cultures of S. sapinea, which was accompanied by a simultaneous decrease in superoxide. The same effect was not observed in T. harzianum. The growth of both fungi was inhibited when h...
D Vesentini, T Singh


Oxidative stress and lignin peroxidase production in Phanerochaete chrysosporium
2008 - IRG/WP 08-10655
In Phanerochaete chrysosporium liquid cultures, the induction of lignin peroxidases is directly related to accumulation of reactive oxygen species at the mitochondrial level. In this study, we demonstrate that the expression of the mitochondrial thiol-related antioxidant system is not directly coupled to the LiPs expression. When the antioxidant systems are not able to cope with ROS accumulation, ...
M Morel, L Diss, C Fourrey, M Chalot, M Droux, J P Jacquot, E Gelhaye


The Use of Micro-Tensile Testing to Assess Weathering Decay and Oxidative Degradation of Wooden Items
2010 - IRG/WP 10-20433
This paper presents a method to study the weathering performance of wooden items and to assess the oxidative degradation of wood via the Fenton reaction. Weathering resistance and photo-stability of wood was tested using pine wood (Pinus sylvestris) veneer strips measuring approximately 60 µm in thickness. The veneer strips were treated using a reactive chemical to impart surface protection. The ...
C Mai, Yanjun Xie, Zefang Xiao, P D Evans, H Militz


Possible targets of wood modification in brown rot degradation
2014 - IRG/WP 14-40676
Wood modification protects wood from fungal degradation in a non-toxic manner. However, the mechanisms behind the decay resistance in modified wood are currently unknown. The aim of this study was to discuss the i) colonisation, ii) nutrient recognition, iii) transcription, iv) depolymerisation and v) hydrolysis steps in the brown rot degradation progress and explore whether they are inhibited by ...
R Ringman, A Pilgård, G Alfredsen, B Goodell, K Richter


Different levels of acetylation lead to groupwise upregulation of non-enzymatic wood degradation genes of Rhodonia placenta during initial brown-rot decay
2020 - IRG/WP 20-10958
Rhodonia placenta, often used as a model fungus to represent brown rot fungi, uses a two-stepped degradation mechanism to degrade wood. Regarding the overcoming of wood protection systems the initial degradation phase seems to be the crucial point. A new laboratory test enables the separation of the non-enzymatic oxidative and the enzymatic degradation phases, which has previously been proven chal...
M Kölle, R Ringman, A Pilgård


Decomposition and metabolism of gaseous COS by wood rotting fungi
2021 - IRG/WP 21-10978
Previous studies on physiology of wood rotting fungi have mostly focused on the metabolisms of carbon and nitrogen sources. On the other hand, despite of the biological importance of minerals such as sulfur, our knowledge of their metabolic systems is limited. The sulfur source for wood-rotting fungi has been thought to be water-soluble sulfur compounds such as sulfate esters and cysteine, which a...
R Iizuka, O Iwao, Y Katayama, M Yoshida


Metabolite analysis of fungal COS degradation and phylogenetic investigation of COSase genes
2023 - IRG/WP 23-11018
Fungi are the major species causing microbial deterioration that reduces the commercial value of wood, such as wood decay and surface contamination, so it is important to accumulate knowledge on the physiology of fungi in order to develop countermeasures against these problems. Most physiological studies of fungi that have been reported have concerned the metabolism of carbohydrates as a source of...
R Iizuka, S Hattori, I Ohtsu, D Hibbett, Y Katayama, M Yoshida