Based on SELEX screening of Escherichia coli K-12 W3110, XynR, formerly known as YagI, was identified as a regulator of xylonate catabolism; it is a rare single-target TF, and its regulation network is still fixed within the CR4-6 prophage without significant cross-talk with the host. It regulates the bidirectional transcripts yagA(b) and yagEF(GH) .
A single peak of XynR binding was identified within the spacer of bidirectional transcription units of the yagA and yagEF operons. However, by decreasing the cutoff of detection, approximately 30 low-level peaks were detected, which are all located inside open reading frames (ORFs) . The level of XynR was detectable in the exponential growth phase, but it decreased to an undetectable level during growth in the stationary phase .
A xynR mutant shows increased biofilm formation compared to wild type, but a lower increase in biofilm formation when the derepressed conjugative plasmid R1drd19 is present .
XynR: xylonate catabolism regulator Read more >