Your search resulted in 8 documents.
The identification and preservative tolerance of species aggregates of Trichoderma isolated from freshly felled timber
1992 - IRG/WP 92-1553
The surface disfigurement of antisapstain treated timber by preservative-tolerant fungi remains a major problem in stored timber. Identification of a range of isolates of Trichoderma based on microscopic morphological characteristics was found to be imprecise due to the variable nature of this organism. In addition, studies to compare visual (morphological) characteristics of these isolates with their tolerance to the antisapstain compound methylene-bis-thiocyanate (MBT) using minimum inhibition concentration (MIC) tests showed no clear correlations. Isoenzyme electrophoresis was used to investigate the taxonomic relationships between species aggregates of Trichoderma isolated from antisapstain field trials and to identify physiological differences between 30 isolates of Trichoderma which show tolerance to MBT at concentrations ranging from less than 4 ppm to 34 ppm. Results indicate that there is considerable variability in the preservative tolerance of different Trichoderma isolates from particular locality. This highlights the need for field testing of an antisapstain compound in the same locality and under the same conditions in which it will be used in practice.
R J Wallace, R A Eaton, M A Carter, G R Williams
Molecular studies on isolates of Serpula lacrymans
1989 - IRG/WP 1421
The major protein species present in detergent extracts of 14 different Serpula lacrymans isolates have been compared, by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE), with a standard strain, viz. Serpula lacrymans FPRL 12C. Following silver staining of SDS gels the major protein species identified in 12 isolates were similar to those found in the standard strain. However differences were found when the final two isolates were compared with FPRL 12C, both isolates had extra molecular species not present in 12C and both were lacking some present in the standard strain. Comparison of the protein species identified in Serpula lacrymans isolates with those identified in extracts of other fungal organisms, viz. brown and white rot causing basidiomycetes and non-basidiomycetes indicated that the Serpula isolates were more similar to each other than to other organisms. Some molecular differences could be identified when individual isolates were cultured on different media, i.e. liquid culture or agar, only minor differences were seen when individual isolates were subcultured. These results indicate that whilst care must be taken to ensure as near identical conditions as possible for culture of organisms if their molecular species are to be compared by SDS-PAGE and silver staining, consistent results can be obtained using this technique. The technique may therefore offer a method of distinguishing between isolates, strains and species of wood decay basidiomycetes, and identifying new isolates.
A Vigrow, D Button, J W Palfreyman, B King, B M Hegarty
Effects of terpene compounds on the growth and peroxidase activity of Phellinus pini
1979 - IRG/WP 2130
The volatile compounds myrcene, limonene, a-pinene, a-terpineol, D-fenchol and 1,8-cineole, present in the oleoresin fraction of coniferous wood, were tested individually and as mixtures for their effect on the growth and peroxidase activity of cultures of six strains of Phellinus pini (Fr.) A.Ames and one strain of Phellinus chrysoloma (Fr.) Donk (Phellinus pini var. abietis (Karst.) Pilát). Phellinus pini was more tolerant of the substances than Phellinus chrysoloma. There were differences in the tolerance and peroxidase activity between the strains of Phellinus pini. Peroxidase activity was generally higher in the test cultures than in the controls, but was lower in cultures exposed to 1,8-cineole and a-terpineol.
Characterization of Poria indoor brown-rot fungi
1995 - IRG/WP 95-10094
The heterogeneous group of "Poria" fungi causing brown rot in buildings and also of wood in ground contact comprises Antrodia vaillantii, Antrodia serialis, Antrodia sinuosa, Antrodia xantha and Tyromyces placenta. These fungi have similar morphological appearance and biology. Their nomenclature has a confusing history and is still not uniform. As a consequence, misinterpretations may occur. SDS polyacrylamide gel electrophoresis showed a species-specific protein pattern for different cultures of Antrodia vaillantii separating the species from the other pore fungi as well as from Coniophora puteana and Serpula lacrymans. Electrophoresis also detected misidentifications. Investigations on growth rate, response to temperature, copper tolerance and wood decay revealed: Radial growth extension reached from 4 to 9 mm/d. Temperature optimum was 25 to 31°C. All withstood 1 hour at 60°C and some even 3 h at 65°C. Antrodia vaillantii was copper tolerant up to 0.05 M Cu. Wood weight loss after 20 weeks was higher by Tyromyces placenta (35%) and Antrodia sinuosa (33%) than by Antrodia xantha (21%), Antrodia serialis (16%) and Antrodia vaillantii (14%). Dual cultures revealed various inter- and intraspecific interactions and detected identity of differently coded cultures of a species. The former Poria vaporaria sensu Liese 'Normstamm II' for testing wood preservatives and the recent Poria placenta EN 113 strain FPRL 280 were shown to be either identical or at least sister monokaryons originating from the same individual.
The antigenic nature of Serpula lacrymans
1991 - IRG/WP 1492
The molecular nature of Serpula lacrymans has been extensively analysed by SDS-PAGE and distinctive banding patterns have been demonstrated. To develop simpler methods for identification of the organism an immunological analysis of a variety of isolates of both Serpula lacrymans and a number of other wood decay basidiomycetes has been undertaken. Results indicate unique antigenic profiles for Serpula lacrymans isolates and indicate that identification by immunological methods is feasible though antisera produced using mycelial extracts as immunogens are highly cross reactive. The antigenic profile for the closely related organism, Serpula himantioides, was very similar to that of Serpula lacrymans. Further antigenic analysis of 1) the organism grown in a variety of media and 2) different morphological forms of the organism have indicated variability in the molecular nature of the major antigens expressed by Serpula lacrymans.
A Vigrow, H Glancy, J W Palfreyman, B King
Characterization and differentiation of wood rotting fungi by protein and enzyme patterns
1999 - IRG/WP 99-20177
Standardized tests for wood preservatives are performed with defined fungal strains to ensure comparability between laboratories. However, changes of virulence and variation of results are well known events. Suitable and reliable measures to control the stability of the test organisms are necessary.Comparison of protein patterns produced by SDS-electrophoresis was already described by several authors as a possible way to identify and to characterize fungal species and strains, i.e. for Serpula, Coniophora and Poria. We compared protein patterns of several strains of Antrodia vaillantii, Poria placenta, Gloeophyllum trabeum, Lentinus lepideus, and Coniophora puteana. Isoelectric focussing and detection of esterase isoenzymes proved to be an alternative method. The investigations resulted in species-specific protein and enzyme patterns. By comparing the strains of single species it was possible to form groups with similar patterns. Possible misidentifications could be detected. The described methods will be further developed and used to follow possible changes in our test strains.
Direct analysis from wood of the blue stain fungi Aureobasidium pullulans and Hormonema dematioides by denaturing gradient gel electrophoresis
2006 - IRG/WP 06-10595
Aureobasidium pullulans and Hormonema dematioides are the two organisms used in the EN 152 laboratory method for determining the effectiveness of preservatives against blue stain in service. The literature concerning the disfigurement of surface coatings and exposed timber in-service states that A. pullulans is the dominant blue stain fungus, due to its frequent isolation from stained material. Inaccuracies when differentiating morphologically between isolates of these two related species have previously been highlighted bringing the conclusion concerning the dominance of A. pullulans to question. PCR-DGGE has been used to determine the environmental profile of the two blue stain fungi; A. pullulans and H. dematioides and to establish which of these organisms is most prevalent on a range of stained timber samples taken from trials and in service. The DGGE analysis indicated that a member of the Dothioraceae family, most likely H. dematioides was more commonly present on stained timber samples under five years old. No blue stain fungi were detectable by PCR-DGGE in older samples over 25 years old. With the correct primer choice PCR-DGGE is able to differentiate between different species and the level of abundance at which those species are represented in a sample. It is clear from this study that A. pullulans is not as dominant on stained timber as would have been expected. On this basis it is suggested that H. dematioides should be the preferred species for research and development work in this field.
M J Ray, D J Dickinson
Characterization of protein patterns from decayed wood of loblolly pine (Pinus taeda L.) by proteomic analysis
2008 - IRG/WP 08-10654
The primary biotic decomposers of wood belong to the basidiomycetes. The members of this group can attack and biodegrade both wood in the forest and in service. By the time wood decay is visible, there has already been a significant loss of strength. The identification of basidiomycetes and other organisms on wood only tell us what is present, not what is actively decaying the wood. When organisms are metabolically active, such as during wood decay, they produce proteins, some of which are unique to the decay process. Detection and identification of the fungal proteins involved in wood biodegradation would be an advantage in helping to understand the complex biodegradation pathways. In this study, we concentrated on proteomics as a tool to decipher biodeterioration-linked proteins. Proteomic analysis of fresh wood (southern yellow pine), decayed wood, inoculated decayed wood, and Gloeophyllum trabeum were performed. More than 170 proteins from four treatments were visualized on Commassie-stained two-dimensional polyacrylamide gels with a high resolution and reproducibility. These protein spots were subjected to in-gel digestion with trypsin for peptide fingerprint analysis by MALDI-TOF-MS. The tryptic peptides were identified with the aid of a BLAST homology search which found 76 unique proteins from inoculated decayed wood. No proteins were detected from fresh wood. Over 110 proteins were visualized from Gloeophyllum trabeum grown in culture. Among the proteins identified were oxidative enzymes and hydrogen peroxidases. Only actin was identified from decayed wood, but inoculated decayed wood contained wood degradation proteins such as alcohol oxidase, lipoxygenase, and catalases.
Young-Min Kang, L Prewitt, S Diehl