Conserved hypothetical BB0462 protein enhances the transcription activity of oppAV promoter

Abstract

Borrelia burgdorferi BB0462 ORF encodes an unknown functional protein with 110 amino acids. A BLAST search in protein databases and the secondary structure being predicted by the program JUFO showed that the conserved hypothetical BB0462 protein was similar to the members of the YbaB protein family in both amino acid composition and protein structure. The co-transformation of BB0462 ORF and oppA upstream regulation DNA into E. coli host cells and β-galactosidase activity assay demonstrated that the BB0462 protein enhanced the transcriptional activity of the oppAV promoter, but does not affect those of oppAI, II, III and IV promoters. Analysis of DNA retardation and competitive repression also confirmed that the BB0462 protein bound to the 409 bp upstream regulation DNA fragment close to the initiation codon of the oppAV gene. All data in our study suggested that the BB0462 protein was involved in the transcriptional regulation of the oppAV gene © 2008 Higher Education Press.