The identity of Penicillium sp. 1, a major contaminant of the stone chambers in the Takamatsuzuka and Kitora Tumuli in Japan, is Penicillium paneum

Penicillium appeared as the major dweller in the Takamatsuzuka Tumulus (TT) and Kitora Tumulus (KT) stone chambers, both located in the village of Asuka, Nara Prefecture, in relation to the biodeterioration of the 1,300-year-old mural paintings, plaster walls and ceilings. Of 662 Penicillium isolates from 373 samples of the TT (sampling period, May 2004–2007) and the KT (sampling period, June 2004–Sep 2007), 181 were phenotypically assigned as Penicillium sp. 1 which shared similar phenotypic characteristics of sect. Roqueforti in Penicillium subg. Penicillium. Fifteen representative isolates of Penicillium sp. 1, 13 from TT and 2 from KT, were selected for molecular phylogenetic analysis. The 28S rDNA D1/D2, ITS, β-tubulin, and lys2 gene sequence-based phylogenies clearly demonstrated that the three known species P. roqueforti, P. carneum and P. paneum in sect. Roqueforti, and all TT and KT isolates grouped together. In addition to this, TT and KT isolates formed a monophyletic group with the ex-holotype strain CBS 101032 of P. paneum Frisvad with very strong bootstrap supports. So far, P. paneum has been isolated only from mouldy rye breads, other foods, and baled grass silage. Therefore, this is the first report of P. paneum isolation from samples relating to the biodeteriorated cultural properties such as mural paintings on plaster walls.