ABSTRACT

Microbial communities colonising monuments can be analysed by culture-dependent and-independent techniques. However, the results obtained from the studies varied considerably. This apparent disparity was investigated using an experimental system composed of common building materials inoculated with a consortium of several bacteria. Culture-independent techniques revealed the presence of a diversity of microorganisms including halophilic bacteria and Archaea, while culture-dependent techniques showed the presence of spore-forming bacteria. The consortium was constituted by cultivable microorganisms able to produce several damages on monuments, such as staining, discoloration, patinas and efflorescences. Culture-dependent techniques detected principally species of Arthrobacter, Bacillus, Paenibacillus, Micrococcus, Staphylococcus and Kocuria, with a predominance of spore-forming bacteria. The application of molecular methods, especially the amplification of 16S rDNA, seems to give a more complete view of the actual bacterial community than traditional culture techniques, since molecular methods enable the detection of slowly growing and fastidious bacteria.