Your search resulted in 43 documents. Displaying 25 entries per page.
Wharf-borer a threat to stored archaeological timbers
1992 - IRG/WP 92-1560
Increased interest in marine archaeology has occured in recent years. Stored waterlogged archaeological timbers have been shown to be degraded by physical and microbial agents. In recent years a new threat has been highlighted, namely the wharf-borer Nacerdes melanura (L.). The objective of this paper is to outline studies of the morphology, biology, life-history and carbohydrate digestion by this...
A J Pitman, E B G Jones, A M Jones, M Rule
A new concept of oxalic acid biosynthesis in physiology of copper-tolerant brown-rot fungi
2001 - IRG/WP 01-10394
Recently, a wide variety of roles of oxalic acid (oxalate) in wood decay systems have been receiving much attention. Copper tolerance of wood-rotting basidiomycetes has been believed to be due to the detoxification of copper wood preservatives by oxalate produced by these fungi. However, biochemical mechanism of oxalate biosynthesis in relation to physiology of wood-rotting fungi has not been eluc...
E Munir, T Hattori, M Shimada
Aspects of the biology of the wood-boring weevil Pselactus spadix herbst
1997 - IRG/WP 97-10221
The external morphology of the adult and larval digestive tract of the wood boring weevil Pselactus spadix has been reported for the first time. An examination of adult gut ultrastructure showed that the foregut was adapted for the wood boring habit with the presence of chitinous setae, grinding plates and sieve plates. The adult midgut bore eight caecae and numerous palpii. Spherical yeast-like m...
G Cooper, A J Pitman, G S Sawyer
Spatial arrangement of lignin peroxidase in pine decayed by Phanerochaete chrysosporium and Fomitopsis pinicola
1988 - IRG/WP 1343
By applying immunoelectronmicroscopic methods, lignin peroxidase of the white rot fungus Phanerochaete chrysosporium has been localized in the cytoplasm of hyphae, close to the plasmalemma and on the plasmalemma. Infiltration of wood specimen with culture filtrates, concentrated 300-fold, gave clear information on the penetration of the enzyme into the wood cell wall. Penetration was restricted to...
E Srebotnik, K Messner
The preliminary characterization of ß-1,4-xylanase of the brown-rot fungus Gloeophyllum trabeum
1990 - IRG/WP 1447
The extracellular ß-1,4-xylanase of the brown-rot fungus, Gloeophyllum trabeum, was isolated from crude extract by chromatofocusing method (PBE 94 column chromatography). The isoelectric point was estimated to 4.2-4.8 by cromatofocusing and 4.5 by isoelectric focusing (IEF). The molecular weight of the enzyme was estimated to 37,000 dalton by SDS-PAGE. The optimal temperature for the crude extrac...
A-C Ritschkoff, M Rättö, L Viikari
Suppression of aerial hypha formation by spent culture filtrate of a non-degradative strain of Postia placenta
1991 - IRG/WP 1498
ME20, a wild-type monokaryotic strain of the brown-rot fungus Postia placenta, does not cause significant weight losses in standard soil-wood block decay tests and fails to form aerial hyphae in liquid and agar culture. This abnormal morphological feature may be caused by the same aberrant physiology that prevents the strain from degrading wood efficiently. ME20 releases elevated levels of the aut...
J A Micales
Evaluation of New Zealand staining fungi for degradation of radiata pine
1999 - IRG/WP 99-10310
This investigation sought to determine the potential of selected NZ staining fungi to induce weight loss and changes in toughness (impact bending strength) and composition in unseasoned radiata pine sapwood. Furthermore, assays were performed to eveluate enzyme production by staining fungi. Sets of side-matched specimens were inoculated with Ophiostoma floccosum, Sphaeropsis sapinea and O. plurian...
A Schirp, R L Farrell, B Kreber
Effect of light and ventilation condition on the rate of wood decay by the brown rot basidiomycete, Tyromyces palustris
1991 - IRG/WP 1517
Effect of light and the ventilation conditions of incubation jars on the wood decay by Tyromyces palustris (Berk. et Curt.) Murr. FFPRI 0507 was investigated. Under no irradiation of light, the ventilation conditions gave extensive effect on mass loss of the test pieces when the culturing was performed with culture medium designated in Japanese Industrial Standard (JIS) A 9302 (Medium A; glucose 4...
T Suzuki, M Higaki
Preliminary studies on cellulase production by selected Basidiomycetes and the effect of copper-chrome-arsenate on these enzymes
1980 - IRG/WP 1122
The growth of wood-destroying fungi on ligno-cellulosic materials depends on the production of many enzymes, of which probably the most important is the multi component cellulase system. Within this system, at least three different kinds of enzym are believed to be involved in crystalline cellulose decomposition. These are endo-1,4-glucanase, exo-1,4-ß glucanase and ß-glucosidase. Most of the re...
The effect of tunicamycin on production and secretion of extracellular carbohydrate-degrading enzymes by Postia placenta
1988 - IRG/WP 1342
The extracellular carbohydrate-degrading enzymes of wood-decay fungi are usually heavily glycosylated and therefore stable under most denaturing conditions. It is unlikely that wood decay can be prevented by simply inactivating these enzymes. Tunicamycin, an antibiotic produced by Streptomyces lysosuperificus, prevents the glycosylation of glycoproteins and can interfere with the secretion of thes...
J A Micales, T L Highley
Molecular analysis of the basidiomycete Coniophora puteana
1992 - IRG/WP 92-1534
Sodium dodecylsulphate polyacrylamide gel electrophoresis and Western Blotting, using a polyclonal antiserum produced against a whole cell extract of Coniophora puteana, were used to analyse the major proteins and antigens of the wet rot organism Coniophora puteana. The macromolecule profiles of this organism were different from other members of the Coniophora genus and from a set of unrelated org...
H E McDowell, D Button, J W Palfreyman
Fenton's reagent as a modification tool in brown-rot decay
1996 - IRG/WP 96-10155
A biomimetic approach was used to clarify the role and importance of the Fenton-type reaction in the carbohydrate degradation by brown-rot fungi. Spruce sawdust and microcrystalline cellulose were modified in the H2O2/Fe(II) treatment. The degree of hydrolysis of the pretreated spruce sawdust was clearly increased with the complete cellulase (Econase), purified endoglucanase from Trichoderma reese...
M Rättö, A-C Ritschkoff, J Buchert, L Viikari
The probable mechanism of action of boric acid and borates as wood preservatives
1990 - IRG/WP 1450
The tetrahydroxyborate ion [B(OH)4-] acts by complexation with poly-ols and probably attacks decay fungi through extracellular substrate sequestration; intracellular substrate sequestration; enzyme inhibition; and change in membrane function. Work was carried out to investigate this further and to try to explain certain phenomena observed in the area of boron preservation. The effect of Na borate ...
J D Lloyd, D J Dickinson, R J Murphy
Biochemical relationships between biodegradation of cellulose and formation of oxalic acid in brown-rot wood decay
1991 - IRG/WP 1472
Non-enzymic hydrolysis of cellulose with low concentrations of oxalic acid was examined. The incubation of pine wood pulp with 1% oxalic acid (pH 1.3) at 35°C for 4 weeks reduced the original viscosity to 60%. Reducing sugars were liberated from various cellulosic samples by the oxalic acid treatment. However, crystallinities of cellulose in those samples did not change before and after the treat...
M Shimada, Y Akamatsu, A Ohta, M Takahashi
Copper storage in the digestive caecae of Limnoria tripunctata and Limnoria quadripunctata (Crustacea: Isopoda) tunnelling in CCA treated and untreated wood in laboratory cultures
1998 - IRG/WP 98-10257
Digestive tract tissues of Limnoria quadripunctata Holthuis and Limnoria tripunctata Menzies, tunnelling untreated and CCA treated Scot's pine sapwood under laboratory conditions were examined using X-ray microanalysis and transmission electron microscopy. Populations of both Limnoria species tunnelling treated and untreated wood stored copper within their digestive caecae in the form of ...
C Wykes, A J Pitman, S M Cragg
Secretion of ligninolytic enzymes by hyphal autolysis of the white rot fungus Phanerochaete chrysosporium
1991 - IRG/WP 1480
The secretion of ligninases by Phanerochaete chrysosporium was investigated with polyclonal antibodies, followed by immmunogold-silver staining and light microscopy. After growing fungal mycelium on nitrocellulose, extracellular ligninases were detected around old, plasmaless hyphae, but not at arthrospores, chlamydospores, or blastoconidia. Labeling of fungal hyphae on coverslip cultures was obse...
R Lackner, E Srebotnik, K Messner
Borate-treated food affects survival, vitamin B12 content, and digestive processes of subterranean termites
1990 - IRG/WP 1448
Toxicity of boron compounds was studied by analyzing survival rates and vitamin B12 contents in Formosan subterranean termites, Coptotermes formosanus Shiraki, that were exposed to dietary treatments for 10 days. The dietary treatments applied in moistened cellulose were (a) 0.05% boric acid equivalent (BAE) of disodium octaborate tetrahydrate, (b) 0.05% BAE of anmonium pentaborate plus sodium sul...
L H Williams, S I Sallay, J A Breznak
Old and new facts on the dry rot fungus Serpula lacrymans
1991 - IRG/WP 1470
The article collates some of the recent literature on the biology of the dry rot fungus Serpula lacrymans. The fungus can grow at 28°C, and maximum wood moisture is above 55%. Serpula Iacrymans degrades crystalline cellulose. The intensive production of extracellular oxalic acid is neutralized by calcium and iron. There is considerable variation among the strains with regard to factors such as gr...
O Schmidt, U Moreth-Kebernik
Breakdown of cellulose derivatives by cellulolytic enzymes. I. Action of fungal ß-glucosidases toward substituted PNP ß-D-glucopyranosides
1998 - IRG/WP 98-10281
The action of fungal ß-glucosidases on the methyl derivatives of p-nitrophenyl (PNP) ß-D-glucopyranoside, which were regioselectively substituted at 0-2, 0-3, 0-4 and 0-6 positions was studied. Several ß-glucosidases from brown-rot, white-rot, and soft-rot fungi and almond were used for the study. These ß-glucosidases did not act on the 2, 3, and 4-0-methyl derivatives, while the 6-0-methyl on...
T Nishimura, I Momohara, M Ishihara
Cytoplasmic and extracellular localization of manganese II dependent peroxidase(s) in white rot fungi during degradation of woody materials
1989 - IRG/WP 1416
The manner by which lignin is degraded in-situ in natural substrates by white rot fungi still remains a controversial issue particularly the distribution and role(s) played by lignin degrading enzymes (i.e. manganese II peroxidase and lignin peroxidase). In the present study, use was made of anti-manganese II peroxidase and immunolabelling techniques in conjunction with transmission electron micro...
G F Daniel, B Pettersson, T Nilsson, J Volc
The nature of osmiophilic particles and their distribution during different stages of brown and white rot decay
1983 - IRG/WP 1213
The distribution of osmiophilic particles during the course of brown and white rot decay was investigated by applying transmission electron microscopic (TEM) methods. It was found that it correlates with the brown and white rot pattern.The osmiophilic particles are produced by the fungus and are supposed to be wood rotting enzymes....
K Messner, H Stachelberger
Wood structure in relation to excessive absorption - a literature survey
1971 - IRG/WP 300
This literature study, composed in connection with 'the structure of wood in relation to the excessive absorption', started from the idea that the subject only could be dealt with successfully if the structure was taken into account in relation to a normal absorption pattern in so far as this knowledge can enlighten the understanding of the abnormal situation. The normal penetrat...
S M Jutte
Comparison of the inhibitory effects of borate, germanate, tellurate, arsenite and arsenate on 6-phosphogluconate dehydrogenase
1991 - IRG/WP 1508
Sodium borate inhibits the enzymatic activity of many dehydrogenases, and it is thought that this is due to the complexation of the borate anion with the coenzyme nucleotide. It has been suggested in the past that complexation of this type, leading to enzyme inhibition and other biological effects, is responsible for the inhibition of fungal growth and consequently the protection of boron treated ...
J D Lloyd, D J Dickinson
A biochemical explanation for the observed patterns of fungal decay in timber
1980 - IRG/WP 1111
Experiments designed to compare the degree of localization of the cellulase enzymes of some white, brown and soft rot organisms are described. The site and nature of binding of the enzymes is discussed. The technique is ellution of mycelium grown in liquid culture with a variety: of agents including acetate buffer, carboxymethyl cellulose solution, borate/glycerol buffer and urea. The mycelium was...
N B Green, D J Dickinson, J F Levy
Production, function and neutralization of oxalic acid produced by the dry rot fungus and other brown rot fungi
1987 - IRG/WP 1330
The formation of oxalic acid by the wood-destroying fungi causing brown rot, is found to be the key which by hydrolysing the hemicellulose brings the cellulose in the tracheid wall in contact with the cellulase enzymes and yeld watersoluble sugars leaving only a lignin skeleton. To control the pH in the substrate the excess oxalic acid is precipitated to water insoluble calcium oxalate by the dry ...