Identification of bacterial cultures from archaeological wood using molecular biological techniques

Anaerobic bacteria were isolated from a 1700-year-old wooden spear shaft, excavated from an archaeological site that dates from the iron age, in the southern part of Jutland, Denmark. The bacteria were cultivated in glucose- and xylose-supplemented media at 14degreesC and 20degreesC. A gene library with 21 clones was constructed by extracting and amplifying 16S rDNA sequences from the individual cultures.

One clone was phylogenetically affiliated to the Spirochaeta. Eleven clones affiliated to an unidentified member of the alpha-Proteobacteria were present in all culture samples. Three clones were affiliated to the beta-Proteobacteria. Four clones were clustered among the Geobacteriaceae, in the delta-Proteobacteria.

A single clone was clustered with gram-positives. All the identified bacterial families are commonly found in soil or bog environments and many are able to utilize cellulose as their carbon or energy source.