BACILLUS DNA IN FOSSIL BEES - AN ANCIENT SYMBIOSIS

We report here the isolation of DNA from abdominal tissue of four exti nct stingless bees (Proplebeia dominicana) in Dominican amber, PCR amp lification of a 546-bp fragment of the 16S rRNA gene from Bacillus spp ., and their corresponding nucleotide sequences. These sequences were used in basic local alignment search tool searches of nonredundant nuc leic acid data bases, and the highest scores were obtained with 16S rR NA sequences from Bacillus spp. Phylogenetic inference analysis by the maximum-likelihood method revealed close phylogenetic relationships o f the four presumed ancient Bacillus sequences with Bacillus pumilus, B. firmus, B. subtilis, and B. circulans. These four extant Bacillus s pp. are commonly isolated from abdominal tissue of stingless bees. The close phylogenetic association of the extracted DNA sequences with th ese bee colonizers suggests that a similar bee-Bacillus association ex isted in the extinct species P. dominicana.