0026-2617/02/7103- $27.00 © 2002 åÄIä “Nauka /Interperiodica” 0350 Microbiology, Vol. 71, No. 3, 2002, pp. 350–356. Translated from Mikrobiologiya, Vol. 71, No. 3, 2002, pp. 409–417. Original Russian Text Copyright © 2002 by Gorbushina, Lyalikova, Vlasov, Khizhnyak. It is known that inorganic construction materials, including marble, limestone, and brick, are contami- nated by various microorganisms, which can deterio- rate these materials [1–4]. Microbial growth on the sur- face of stones promotes their weathering, gives rise to pigmented biofilms and incrustations, and causes mar- ble exfoliation [5]. Biofilms are communities of micro- organisms which beneficially influence each other through the secretion of extracellular substances (such as pigments, polysaccharides, and proteins), thereby providing for biofilm development on the surface of solid mineral substrates. Marble damage is very exten- sive in urban environments, where dust particles inter- act with microbial films, giving rise to firm incrusta- tions on the surface of marble [6, 7]. The excretion of acids by autotrophic (nitrifying and thionic) and het- erotrophic bacteria promotes the superficial leaching of marble. Recent studies revealed the significant role of micromycetes in the deterioration of antique and medi- eval marble monuments in the Mediterranean countries [8–10], the Crimea [11], and northern Europe [12]. Microcolonial pigmented fungi can grow on and in the superficial layer of marble and other calcareous rocks and cause their deterioration [9]. Marble monuments in the open air are also often contaminated by the propagules of soil fungi, which begin growing and col- onizing marble’s surface under favorable environmen- tal conditions. It is evident from this survey, that the extent of stone deterioration depends not only on the surrounding conditions but also on the composition of stone-inhabiting microflora. Numerous open-air marble sculptures and monu- ments in St. Petersburg are exposed to the direct action of atmospheric factors and microorganisms. The inves- tigation of the microbial weathering of stone historical heritage showed that marble is the most severely con- taminated constructional stone and that the most abun- dant groups of microorganisms inhabiting damaged marble are thiobacteria, molds, and actinomycetes [1]. Wollenzien et al. attempted to isolate some micro- mycetes (Cladosporium, Urocladium, and yeastlike dark-pigmented hyphomycetes) from the samples of Carrara marble taken from the Alexander Nevsky Abbey [9]. In spite of progress in this problem, little is known on the species composition of the microflora inhabiting stone monuments and buildings. The aim of the present work was to investigate the species composition of the microorganisms that inhabit historical marble and limestone sculptures and monu- ments situated in Moscow and St. Petersburg with due consideration for trophic relations between the micro- organisms. MATERIALS AND METHODS Samples for analysis were collected from marble and limestone monuments situated in the Alexander Nevsky Abbey, the Summer Garden, and the Smolen- skoe Cemetery, St. Petersburg, and the Novodevichy EXPERIMENTAL ARTICLES Microbial Communities on the Monuments of Moscow and St. Petersburg: Biodiversity and Trophic Relations A. A. Gorbushina*, N. N. Lyalikova**, D. Yu. Vlasov*, and T. V. Khizhnyak** *Laboratory of Lower Plants, Biological Research Institute, Stary Peterhof, St. Petersburg, Russia **Institute of Microbiology, Russian Academy of Sciences, pr. 60-letiya Oktyabrya 7, k. 2, Moscow, 117811 Russia Received March 27, 2001; in final form, July 9, 2001 Abstract—Stone monuments situated in the Alexander Nevsky Abbey, the Summer Garden, and the Smolen- skoe Cemetery, St. Petersburg, and marble and limestone sculptures and tombstones situated in the Novode- vichy Convent and the Donskoy Monastery, Moscow, were investigated for their microbial contamination. The architectural objects studied date back to the 12th century. The monuments in the Alexander Nevsky Abbey were found to be severely contaminated with micromycetes belonging to 24 genera (primarily of the class Deu- teromycetes). The analysis of the samples taken from the monuments of the Donskoy Monastery by the serial dilution technique showed that they were contaminated with bacteria at a density of (1–1.7) × 10 5 cells/g. This value, however, turned out to be 1 to 2 orders greater when the bacterial population was evaluated by the luciferin–luciferase method. We succeeded in identifying 12 bacterial genera; however, this number may be increased in the course of further studies. Some preventive measures to control the biodeterioration of stone heritage are discussed. Key words: monuments, biodeterioration, micromycetes and bacteria able to grow on marble and limestone.