AxyR, an AraC family transcriptional activator of the xylanase 3 gene, requires xylo-oligosaccharides as a cofactor for DNA binding in Paenibacillus sp. strain W-61

Abstract

The xylanolytic bacterium Paenibacillus sp. strain W-61 encodes three extracellular xylanase genes, xyn1, xyn3, and xyn5. In this study, we identified a transcriptional activator required for transcription of the xyn3 gene in strain W-61. The activator, AxyR, contained the highly homologous AraC-type DNA binding domain and required xylobiose, xylotriose, or xylotetraose as cofactor for binding to the xyn3 promoter region.