3 Random amplified polymorphic DNA assay on genomes of biofilm-forming and non-forming Prevotella intermedia

Abstract

Previously we demonstrated up-regulated transcriptional levels of several stress response genes in biofilm-forming Prevotella intermedia (P. intermedia) using microarray analysis and quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR). To further investigate the biofilm formation-gene expression relay system in P. intermedia, we obtained a biofilm-non-forming mutant by exposing P. intermedia strain OD 1-16, a biofilm-forming clinical isolate to ethidium bromide (EtBr), and performed comparative genome analyses in OD 1-16 and a mutant by means of random amplified polymorphic DNA assay (RAPD). In this study, we obtained one mutant that lacked the ability to form biofilm from EtBr-treated OD 1-16 cultures and designated it as strain 171. RAPD revealed that strain 171 had a mutation in a gene encoding trpG type glutamine amidotransferase. The results indicated that this gene might be involved in the biofilm formation of this organism.