FORMATS
HTML
EDITORIAL REVIEWS
Product Description This digital document is a journal article from International Biodeterioration & Biodegradation, published by Elsevier in 2006. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser. Description: There are few modern analyses of the cyanobacterial communities in biofilms on external building surfaces. As the classification of cyanobacteria is rapidly changing, we aimed to identify them on historic buildings in Brazil using both established and molecular techniques. In mature biofilms, cyanobacteria of subsections I and II were generally the major biomass; occasionally filamentous genera of the Scytonemataceae, Microchaetaceae and Rivularaceae were dominant. Filamentous organisms of subsections III and IV were more frequently isolated in culture. PCR products using cyanobacteria-specific 16S rDNA primers were sequenced from morphologically identified organisms. Homologies with deposited sequences were generally low. Phylogenetic analysis showed that many isolates were distant from their nearest neighbours, even though they grouped with their appropriate taxa. The majority of cyanobacterial DNA sequences deposited in data banks are aquatic; our results indicate that cyanobacteria from external walls are an ecologically isolated group.