Bacteria Restores 14th Century Italian Frescoes

Bacteria has been successfully used to restore a fresco by Spinello Aretino, depicting the Conversion of St. Efisio, at the Camposanto cemetery in Pisa. Discovery News reports that the bacteria, Pseudomonas stutzeri, was used to restore damage following an accidental American bombing of the Camposanto cemetery in 1944, and subsequent attempts to restore the frescoes -- detatching them from the walls and then gluing them to canvas on asbestos frames, exposure to weather, and the use of ammonium carbonate as a cleaning solvent -- which had caused much of the paint to dissolve.

Researchers plan to use similar bacteria to remove black crust from limestone and marble monuments, including the Theatre of Epidaurus in Greece.