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The potential of immunological probes, viz. antisera, as specific detection systems for the basidiomycete organisms Lentinus lepideus (a major cause of distribution pole failure) and Coriolus versicolor have been investigated. Using immunodot-blot techniques semi¬quantitative detection systems have been developed for the former organism and immunocytochemical techniques for the latter, allowing its visualisation in wood. Specificity studies on the antisera produced indicate that cross reactivity is limited to basidiomycetes, and in particular specific brown and white rot organisms. Cross reactivity can be diminished by suitable absorption. Western blot studies on L. lepideus indicate that the organism contains a number of antigenic species. Immunological methods are appropriate to research in the biodeterioration of wood and will prove valuable in the detection and identification of decay microorganisms.

A range of isolates of Serpula lacrymans show identical molecular profiles by Western Blotting or lectin staining. One isolate, BF-050, showed differences in silver stained protein profiles from old mycelium but profiles from young mycelium of BF-050 were identical to the type strain of S. lacrymans FPRL 12C. Both S. lacrymans and the related organism, Serpula himantoides, shared different profiles for old and young mycelium confirming that growth phase antigens/proteins are not limited to S. lacrymans. Lectin staining profiles could distinguish between S. lacrymans FPRL 12C, BF-015B, S. himantoides and all other basidiomycete organisms tested. Differences between strains of S. lacrymans including BF-050, were not apparent.

Antigenic proteins from isolates of Serpula lacrymans isolated from locations around the world and from other wood decaying basidiomycetes were compared after Western blotting using an antiserum produced against S. lacrymans strain FPRL 12C. All isolates of S. lacrymans gave identical antigen profiles. A further isolate, originally identified as S. lacrymans , gave a slightly different profile but was almost certainly an isolate of the closely related organism Serpula himantioides . All other organisms gave very different antigenic profiles indicating that identification of species would be possible using immunoblotting. The major antigens of S. lacrymans , grown in liquid culture, were represented in the immunoblots as broad, somewhat indistinct, bands and the antigenic profiles of many of the other basidiomycetes also showed this characteristic. In contrast the major antigens extracted from both S. lacrymans infected wood and actively growing regions of mycelial cultures of the organism were represented by discrete bands. However the overall antigenic profiles of each of these extracts were similar to that of the organism cultured in liquid medium in terms of the actual antigenic species present.

Summary The Wood Research Group at Dundee Institute of Technology is currently investigating a number of parameters associated with methodology for) the preservation of timber and the detection of decay organisms within timber. Application of specific methodologies allowing the in situ treatment of timbers with preservative agents and the relatively non-destructive testing of timbers for decay organisms are particularly appropriate to conservation strategies for wooden structures. Currently used procedures for remedial treatment of such structures require visual identification of decayed wood followed by removal and replacement of defective timbers. An alternative strategy is required where artefacts of historical or archaeological importance are under threat. The development of immunological methods for the detection of incipient decay (i.e. the presence of decay organisms before they have caused damage to timber) and the use of water soluble diffusible biocides such as boron based salts will be discussed in this presentation. Applications of these methods to two historical artefacts present in Dundee, viz. the UNICORN, the oldest surviving European built warship still afloat, and the DISCOVERY, a research ship used in Antarctic exploration in the early part of this century, will also be discussed.

Scanning laser densitometry was performed on immuno- and dot blots developed on nitrocellulose by treatment of the nitrocellulose with xylene. This method permits the development of simple methods for recording results of immunoblots and of producing semi-quantitative assays from dot blots.