Serpula (fungus) are formed. The strand mycelium of "Serpula", which can be up to 8 mm thick, are invasive and can spread over non-nutritive surfaces to find new food sources, even spreading through pores in stone, brickwork, and cement. After its initial growth period, the fungus can produce the water it needs and can continue growth into dry timber, eventually degrading it to powder—hence the term "dry rot". "S. lacrymans" is the most serious cause of building timber decay in the UK and northern Europe. The "Dictionary of the Fungi" (10th edition, 2008), suggests that the genus contains two species. , the
Atromentin 4-HPP to observe the formation of atromentin. This was followed by characterization of the enzyme GreA in "Suillus grevillei", six (InvA1-6, of which InvA1, 2 and 5 were functional) in "Paxillus involutus", and NPS3 from "Serpula lacrymans". In addition, there is another adjacent and conserved gene encoding for an alcohol dehydrogenase/oxidoreductase whose function is unclear. In most cases the clustered biosynthetic genes are found orthologous in basidiomycetes. A common promoter motif was found shared between the atromentin synthetase and aminotransferase of 23 different atromentin-producing basidiomycetes that was in almost all cases absent from the alcohol dehydrogenase, indicating co-regulation of the